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Question
The marks scored by 40 students of class IX in mathematics are given below:
81, 55, 68, 79, 85, 43, 29, 68, 54, 73, 47, 35, 72, 64, 95, 44, 50, 77, 64, 35, 79, 52, 45, 54, 70,
83, 62, 64, 72, 92, 84, 76, 63, 43, 54, 38, 73, 68, 52, 54.
Prepare a frequency distribution with class size of 10 marks.
Solution
| Marks | Tally marks | Frequency |
| 20-30 | | | 1 |
| 30-40 | ||| | 3 |
| 40-50 | ||||| | 5 |
| 50-60 | ||||| ||| | 8 |
| 60-70 | ||||| ||| | 8 |
| 70-80 | ||||| |||| | 9 |
| 80-90 | |||| | 4 |
| 90-100 | || | 2 |
| Total = 40 |
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