Mathematics
Marks obtained by 40 students in a short assessment is given below, where a and b are two missing data :
| Marks | No. of students |
|---|---|
| 5 | 6 |
| 6 | a |
| 7 | 16 |
| 8 | 13 |
| 9 | b |
If the mean of the distribution is 7.2, find a and b.
Related Questions
Category Wages in ₹ per day No. of workers A 50 2 B 60 4 C 70 8 D 80 12 E 90 10 F 100 6 G 110 8 (i) Calculate the mean wage, correct to nearest rupee.
(ii) If the number of workers in each category is doubled, what would be the new mean wage?
If the mean of the following distribution is 7.5, find the missing frequency f :
Variate Frequency 5 20 6 17 7 f 8 10 9 8 10 6 11 7 12 6 Calculate the mean of the following distribution :
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