Mathematics
The mean of the following frequency distribution is 57.6 and the sum of all the frequencies is 50. Find the values of p and q :
| Classes | Frequency |
|---|---|
| 0 - 20 | 7 |
| 20 - 40 | p |
| 40 - 60 | 12 |
| 60 - 80 | q |
| 80 - 100 | 8 |
| 100 - 120 | 5 |
Related Questions
A class teacher has the following absentee record of 40 students of a class for the whole term. Find the mean number of days a student was absent.
No. of days No. of students 0 - 6 11 6 - 10 10 10 - 14 7 14 - 20 4 20 - 28 4 28 - 38 3 38 - 40 1 If the mean of the following distribution is 24, find the value of a :
Marks Number of students 0 - 10 7 10 - 20 a 20 - 30 8 30 - 40 10 40 - 50 5 The following table gives the life time in days of 100 electricity tubes of a certain make :
Lifetime in days No. of tubes less than 50 8 less than 100 23 less than 150 55 less than 200 81 less than 250 93 less than 300 100 Find the mean lifetime of electricity tubes.
Using the information given in the adjoining histogram, calculate the mean correct to one decimal place.
