1. Observe the information's in the following cumilative frequency table
no. of days absent
less than 5
less than 10
less than 15
less than 20
less than 25
less than 30
less than 35
less than 40
less than 45
No. of students
29
224
465
582
634
644
650
653
655
Q.. Draw a 'less than' ogive and 'more than' ogive to represent the above data .
Q... Find median for the above data by interpreting the graph.
Q...why regularity is essential in students life (VBQ)
| Class intervals | Frequency | Cumulative frequency less than | cumulative frequency more than |
| 0-5 | 29 | less than 5 = 29 | more than 0 = 655 |
| 5-10 | 195 | less than 10 = 224 | more than 5 = 626 |
| 10-15 | 241 | less than 15 = 465 | more than 10 = 431 |
| 15-20 | 117 | less than 20 = 582 | more than 15 = 190 |
| 20-25 | 52 | less than 25 = 634 | more than 20 = 73 |
| 25-30 | 10 | less than 30 = 644 | more than 25 = 21 |
| 30-35 | 6 | less than 35 = 650 | more than 30 = 11 |
| 35-40 | 3 | less than 40 = 653 | more than 35 = 5 |
| 40-45 | 2 | less than 45 = 655 | more than 40 = 2 |
For less than Ogive, we plot the following points :
(5,29); (10, 224); (15, 465); (20, 582); (25, 634); (30, 644), (35, 650); (40, 653) and (45, 655).
For more than Ogive, we plot the following points :
(0,655);(5,626); (10,431); (15,190); (20,73); (25,21); (30, 11); (35,5) and (40, 2).
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From the intersection of two Ogives, we draw a perpendicular on x - axis, that meets x-axis at 12.15.