Advertisements
Advertisements
प्रश्न
Find the mean of the following frequency distribution by the short cut method :
| Class | 1-10 | 11-20 | 21-30 | 31-40 | 41-50 | 51-60 | 61-70 |
| Frequency | 7 | 10 | 14 | 17 | 15 | 11 | 6 |
उत्तर
| Class Interval | xi | fi | A = 35.5 d = x - A |
fid |
| 1-10 | 5.5 | 7 | -30 | -210 |
| 11-20 | 15.5 | 10 | 20 | -200 |
| 21-30 | 25.5 | 14 | -10 | -140 |
| 31-40 | A = 35.5 | 17 | 0 | 0 |
| 41-50 | 45.5 | 15 | 10 | 150 |
| 51-60 | 55.5 | 11 | 20 | 220 |
| 61-70 | 65.5 | 6 | 30 | 180 |
| Total | 80 | 0 |
`barx = A + (Σf_i d)/(Σf_i)`
`barx = 35.5 + 0/80`
`barx = 35.5 + 0`
`barx = 35.5`
∴ Mean = 35.5
APPEARS IN
संबंधित प्रश्न
Find the mean of the natural numbers from 3 to 12.
If each number given in (a) is diminished by 2, find the new value of mean.
A boy scored following marks in various class tests during a term; each test being marked out of 20.
15, 17, 16, 7, 10, 12, 14, 16, 19, 12 and 16
What are his total marks?
The data on the number of patients attending a hospital in a month are given below. Find the average (mean) number of patients attending the hospital in a month by using the shortcut method. Take the assumed mean as 45. Give your answer correct to 2 decimal places.
| Number of patients | 10 - 20 | 20 - 30 | 30 - 40 | 40 - 50 | 50 - 60 | 60 - 70 |
| Number of Days | 5 | 2 | 7 | 9 | 2 | 5 |
What is the median of 7, 10, 7, 5, 9, 10?
If the mean of 8 , 14 , 20 , x and 12 is 13, find x.
Find the mode of the following:
3, 4, 5, 7, 6, 3, 5, 4, 3, 5, 6, 4, 7, 5, 4, 5, 4, 3, 4, 5, 7, 6, 5, 6, 6, 7
Estimate the median, the lower quartile and the upper quartile of the following frequency distribution by drawing an ogive:
| Age( in yrs) | Under 10 | Under 20 | Under 30 | Under 40 | Under 50 | Under 60 |
| No. of males | 6 | 10 | 25 | 32 | 43 | 50 |
Find the median of 17, 23, 36, 12, 18, 23, 40 and 20
In a given data, arranged in ascending or descending order, the middle most observation is called ______.
