Mathematics
The following table gives the marks scored by a set of students in an examination. Calculate the mean of the distribution by using the short cut method.
| Marks | Number of students |
|---|---|
| 0 – 10 | 3 |
| 10 – 20 | 8 |
| 20 – 30 | 14 |
| 30 – 40 | 9 |
| 40 – 50 | 4 |
| 50 – 60 | 2 |
Related Questions
Using short cut method, compute the mean height from the following frequency distribution :
Height (in cm) Number of plants 58 15 60 14 62 20 65 18 66 8 68 5 The number of match sticks contained in 50 match boxes is given below :
Number of match sticks Number of boxes 40 6 42 7 43 12 44 9 45 10 48 6 (i) Using short cut method, find the mean number of match sticks per box.
(ii) How many extra match sticks are to be added to all the contents of 50 match boxes to bring the mean exactly equal to 45 match sticks per box?
Given below are the daily wages of 200 workers in a factory :
Daily Wages (in ₹) Number of Workers 240 – 300 20 300 – 360 30 360 – 420 20 420 – 480 40 480 – 540 90 Calculate the mean daily wages.
If the mean of the following distribution is 24, find the value of a.
Marks No. of students 0 – 10 7 10 – 20 a 20 – 30 8 30 – 40 10 40 – 50 5