Slide 3: Stem-and-Leaf Plots Slide 6: Mini Lesson: What If Slide 8: Mini Lesson Key 1 Slide 9: Mini Lesson: Key 2 Slide 10: Histogram Slide 12: Mini Lesson: The Difference Between BarGraphs and Histograms Slide 13: Back to Back Stem-and-Leaf Plot Slide 17: Box-and-Whisker Plot Slide 20: Mini Lesson: Box PositionTable of Contents
Example Problem: In the town of Sugar Pine, the next hightemperatures for the next ten days are below. 63 F°, 63 F°, 65 F°, 66 F°, 73 F°, 75 F°, 78 F°, 81 F°,81 F°, 82 F° Now we need to look at all the differentnumbers in the tenth place on the next slide.Stem-and-Leaf Plots
63, 63, 65, 66, 73, 75, 78, 81, 81, 82 Now we need to look at all the differentnumbers that aren’t in the one’s place, there is6, 7 & 8. We will place these on one side of theline and place the numbers that were tied tothose numbers on the other side of the line onthe next slide.Stem-and-Leaf Plots
6 3 3 5 67 3 5 88 112Stem-and-Leaf Plots Now that that is done, we need to give it theright format with a title, units and key. This will beon slide 7.Note: There are not any spaces between the numbers.
If one of the temperatures had been 9 F° and ifone had been 134 F° and if one had been3445 F°, it would have been looking like thebelow.Mini Lesson: What If0 91 343 445
6 3 3 5 67 3 5 88 112High Temperatures For the Next Ten Days(Degrees Fahrenheit) Key: 6 I 3 = 63
A key can be ANY number in the problem.Mini Lesson Key 1
A key tells you what is between the lines, anexample could be if you were working withdecimals and you had the whole number on theleft side and the other number on the other side.If your key number was 1.9 then the key wouldlook like 1 I 9 = 1.9Mini Lesson: Key 2
We will use the same set of numbers 63 F°, 63 F°, 65 F°, 66 F°, 73 F°, 75 F°, 78 F°, 81 F°,81 F°, 82 F° We will arrange these on a graph, instead ofcategories we will have number ranges, for thisone I will use a number range of 10, the amountof numbers that fit into that range will add up onthe bar.Histogram
High Temperatures Forthe Next Ten Days60 - 69 70 - 79 80 - 891234567Frequency(Degrees Fahrenheit)
Mini Lesson: The Difference BetweenBar Graphs and Histograms The key differences are that the bars touch in ahistogram and they don’t in a bar graph.Another example is that the categories on a bargraph are words and on a Histogram they arenumbers.
The back to back stem-and-leaf plot shows theprices (in dollars) of Poodles and Chihuahuas ata breeder. Compare the prices of adoption forthe two dogs. This plot is on the next page.Back to Back Stem &Leaf Plot
Poodle3 1 07 5 58 7 6 5 48 8 5 5Back to Back Stem &Leaf Plot4567Chihuahua0 0 2 3 31 1 2 3 5 50 2 22Key: 4 I 6 I 0 = $64, $60So this is how it works, cover up the Poodle side with your hand. Look at the other stem-and-leaf plot on slide 5, don’t they look similar? You read the Chihuahua side like the otherplot was read. To read the Poodle plot, cover up the Chihuahua side and imagine the“middle column” on the left side.The key is read much the same way, when you cover up the 4 and look on the other sideof the equal, you see $60. When you cover up the 0 and switch the 4 and 6 with your eyes,you see 64 or $64.
Poodle3 1 07 5 58 7 6 5 48 8 5 5Back to Back Stem &Leaf Plot4567Chihuahua0 0 2 3 31 1 2 3 5 50 2 22Key: 4 I 6 I 0 = $64, $60Now we need to find the median of the prices of Poodles and the median of prices forChihuahuas. To do this we will cross out the right and left sides of each one separately tofind the middle or median.Poodle Median: 67Chihuahua Median: 53Conclusion: In general, Poodles cost more than Chihuahuas from breeders.
Find the median, lower quartile and higherquartile. Also find the maximum and minimum.Box-and-Whisker Plot
20 22 27 31 46 47 54Median: 31, the number that splits it in half.Lower Quartile: 22, the half of the smaller numbersHigher Quartile: 47, the half of the larger numbersMinimum: 20, smallest number.Maximum: 54, biggest number.Now you need to place these things on anumbered line (next slide).Box-and-Whisker Plot