This document shows the steps to find the median, lower quartile, and upper quartile from a double stem-leaf plot comparing test results of two classes. It finds the lowest score is 51, highest is 89, and median is 61 for Class B. The lower quartile is 55.5 and the document shows finding the upper quartile.

1. - Mr Kim

2. Before viewing this lesson, please view:
Finding Interquartile Range from Stem-Leaf Plot 1
Finding Interquartile Range from Stem-Leaf Plot 2

3. Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

4. Here’s an example of
Double-Stem Leaf Plot
comparing two classes’ test
results
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

5. We need to find the Median,
Lower and Upper Quartile,
Lowest and Highest score to
draw a Box-Whisker Plot
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

6. To skip to drawing
Box-Whisker Plot, go to
slide number 113
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

7. Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Let’s look at Class B first

8. Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
The Lowest score is…

9. Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
The Lowest score is 51

10. Lowest Score: 51
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

11. Lowest Score: 51
The Highest score is…
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

12. Lowest Score: 51
The Highest score is 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

13. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

14. Lowest Score: 51
Highest Score: 89Now, let’s find the
Median
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

15. Lowest Score: 51
Highest Score: 89Remember the directions
when crossing off
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

16. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“In”

17. Lowest Score: 51
Highest Score: 89
“Out”
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

18. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“In”

19. Lowest Score: 51
Highest Score: 89
“Out”
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

20. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“In”

21. Lowest Score: 51
Highest Score: 89
“Out”
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

22. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“In”

23. Lowest Score: 51
Highest Score: 89
“Out”
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

24. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“In”

25. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“Out”

26. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

27. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
So the Median is in
between 60 and 62
which is …

28. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
So the Median is in
between 60 and 62
which is 61

29. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61

30. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61
Now find the Lower
Quartile

31. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61
Don’t forget to divide
the sides correctly

32. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61
Don’t forget to divide
the sides correctly

33. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61
Find the Lower Quartile

34. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61“In”

35. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61“Out”

36. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61“In”

37. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61“Out”

38. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61

39. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61
So the Lower Quartile is
in between 53 and 58
which is …

40. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61
So the Lower Quartile is
in between 53 and 58
which is 55.5

41. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61
Lower Quartile:
55.5

42. Lowest Score: 51
Highest Score: 89
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Median: 61
Lower Quartile:
55.5
Find the Upper Quartile

43. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“In”

44. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“Out”

45. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“In”

46. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
“Out”

47. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9

48. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
So the Upper Quartile is
in between 64 and 74
which is …

49. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
So the Upper Quartile is
in between 64 and 74
which is 69

50. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69

51. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Also note, Class B data is
Positively Skewed since…

52. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Also note, Class B data is
Positively Skewed since it’s
leaning towards the Left

53. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Also note, Class B data is
Positively Skewed since it’s
leaning towards the Left

54. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69

55. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Now let’s look at Class A

56. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest score is…

57. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest score is 51

58. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
You read backwards 

59. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51

60. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest score is…

61. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest score is 87

62. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87

63. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87 Now, let’s find the
Median

64. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87 Remember the directions
when crossing off

65. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“In”

66. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“Out”

67. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“In”

68. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“Out”

69. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“In”

70. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“Out”

71. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“In”

72. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“Out”

73. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“In”

74. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“Out”

75. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“In”

76. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“Out”

77. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“In”

78. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
“Out”

79. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87

80. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
So the Median is …

81. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
So the Median is 74

82. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74

83. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Now find the Lower
Quartile

84. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Don’t forget to divide
the sides correctly

85. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Don’t forget to divide
the sides correctly

86. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Find the Lower Quartile

87. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74 “In”

88. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74 “Out”

89. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74 “In”

90. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74 “Out”

91. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74 “In”

92. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74 “Out”

93. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74

94. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
So the Lower Quartile
is…

95. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
So the Lower Quartile
is 63

96. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63

97. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
Find the Upper Quartile

98. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
“In”

99. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
“Out”

100. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
“In”

101. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
“Out”

102. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
“In”

103. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
“Out”

104. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63

105. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
So the Upper Quartile
is…

106. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
So the Upper Quartile
is 85

107. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85

108. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
Also note, Class A data is
Negatively Skewed since…

109. Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Lowest Score: 51
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
Also note, Class A data is
Negatively Skewed since it’s
leaning towards the Right

110. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
Also note, Class A data is
Negatively Skewed since it’s
leaning towards the Right

111. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
If you find that confusing,
since most of the scores are
on the higher end, it is
Negatively Skewed

112. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85

113. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Class A Class B
2 1 5 1 2 3 8 9
3 0 6 0 2 4 4
8 6 4 4 2 0 7 4 5
7 6 6 5 3 8 9
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
Now that we have our
details, let’s draw our
Box-Whisker Plot

114. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85

115. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
Our smallest number here
is…

116. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
Our smallest number here
is 51

117. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
And our biggest number
is…

118. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
And our biggest number
is 89

119. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
So we are going to draw a
scale starting from 50

120. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
So we are going to draw a
scale starting from 50
50

121. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50
And go up by 5s until we
reach 90

122. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
And go up by 5s until we
reach 90
50 55

123. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
And go up by 5s until we
reach 90
50 55 60

124. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
And go up by 5s until we
reach 90
50 55 60 65 70

125. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
And go up by 5s until we
reach 90
50 55 60 65 70 75 80 85 90

126. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90

127. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
Now, let’s start with
the Right side
50 55 60 65 70 75 80 85 90

128. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Put a line on 51 on
the scale above

129. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Put a line on 51 on
the scale above

130. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Because 51 is about
there

131. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Now, put a line on
89

132. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Now, put a line on
89

133. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Now put a bigger
line on 55.5

134. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Now put a bigger
line on 55.5

135. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
As well as on 61

136. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
As well as on 61

137. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And 69

138. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And 69

139. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And finally, connect
the lines

140. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And finally, connect
the lines

141. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And finally, connect
the lines

142. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And finally, connect
the lines

143. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
That’s one Box-Whisker
Plot complete

144. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Now, let’s do the
Left side

145. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Repeat the same
steps

146. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
But draw the lines above
the Box-Whisker Plot

147. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Put a line on 51

148. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Put a line on 51

149. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Put a line on 87

150. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Put a line on 87

151. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
Bigger line on 63

152. Bigger line on 63
Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90

153. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And 74

154. And 74
Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90

155. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And 85

156. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And 85

157. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And finally, connect
the lines

158. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And finally, connect
the lines

159. Lowest Score: 51 Lowest Score: 51
Highest Score: 89
Median: 61
Lower Quartile:
55.5
Upper Quartile:
69
Highest Score: 87
Median: 74
Lower Quartile:
63
Upper Quartile:
85
50 55 60 65 70 75 80 85 90
And that’s how you draw
Double Box-Whisker Plot
from Double Stem-Leaf
Plot!