Mathematics
Calculate the mean of the distribution given below using the short cut method.
| Marks | No. of students |
|---|---|
| 11 - 20 | 2 |
| 21 - 30 | 6 |
| 31 - 40 | 10 |
| 41 - 50 | 12 |
| 51 - 60 | 9 |
| 61 - 70 | 7 |
| 71 - 80 | 4 |
Related Questions
The data on the number of patients attending a hospital in a month is given below. Find the average (mean) number of patients attending the hospital in a month using the short cut method.
Take assumed mean as 45. Give your answer correct to 2 decimal places.
Number of patients Number of days 10 - 20 5 20 - 30 2 30 - 40 7 40 - 50 9 50 - 60 2 60 - 70 5 The following table gives the daily wages of workers in a factory :
Wages in ₹ No. of workers 45 - 50 5 50 - 55 8 55 - 60 30 60 - 65 25 65 - 70 14 70 - 75 12 75 - 80 6 Calculate their mean by short cut method.
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