In early civilizations, counting systems typically began as groups of lines to represent numbers. Over time, specific numeral names and symbols were assigned in systems like India or alphabetic letters in Rome. Ancient Babylon used a base-60 sexagesimal system instead of the base-10 decimal system common today.

2. In all early civilizations, the first expression of
mathematical understanding appears in the form
of counting systems. Numbers in very early
societies were typically represented by groups of
lines, though later different numbers came to be
assigned specific numeral names and symbols
(as in India) or were designated by alphabetic
letters (such as in Rome). Although today, we
take our decimal system for granted, not all
ancient civilizations based their numbers on a
ten-base system. In ancient Babylon, a
sexagesimal (base 60) system was in use.

3. Types
HISTOGRAM Frequency
Polygon
Frequency Less than Ogive
curve curve
More than
Ogive curve

4. Simply click on the title to go to the
respective slide.
1. Histogram
2. Frequency curve
3. Method to find the mode
4. Example for mode
To view the slide in
STANDARD order
click here--

5. Simply click on the title to go to the
respective slide.
1. Histogram
2. Frequency curve
3. Method to find the MODE
4. Example for mode
To view the slide in
STANDARD order
click here--

6. What is a histogram?
A histogram is a display of
statistical information that
uses rectangles to show the
frequency of data items in
successive numerical

7. •Construct a frequency polygon table for the following data of weight in
grams, using equal class intervals.
•Observations:
45,55,30,80,75,85,40,60,65,40,60,75,70,60,70,85,85,80,35,45,40,40,60,60,55,
45,30,80,85,75.
Class interval Tally marks Frequency
30-40 ||| 3
40-50 |||| | 6
50-60 ||| 3
60-70 |||| | 6
70-80 |||| 5
80-90 |||| || 7
Total 30

8. Histogram
8
7
6
5
4
Frequency
3
2
1
0
30 40 50 60 70 80 BACK

9. Draw a frequency curve and a frequency polygon
Marks Frequency
0-10 5
10-20 11
20-30 19
30-40 21
40-50 16
50-60 10
60-70 8
70-80 6

10. FREQUENCY CURVE
25
On X-axis
20 1cm=50 marks
On y-axis
1cm=5 students
15
10 FREQUENCY
5
0
0 20 40 60 80 100

11. Frequency Polygon
25
Scale-
20 On X-axis
1cm=20
students
15
On Y-axis
1cm=5 marks
10
5
0
0 20 40 60 80 100 BACK

12. 1. Plot the normal histogram
2. Join the four vertices of the bar with
highest frequency
3. Draw lines to intersect each other
4. Trace them to the base line
5. This point is the median
BACK

13. Chest in cm No. of students
68-74 5
75-81 31
82-88 40
89-95 20
95-102 3
103-109 1

14. MODE
frequency 84.5
45
40
35
30
25
20
15
10 frequency
5
0