Advertisements
Advertisements
प्रश्न
The mean of the following distribution is `21 1/7`. Find the value of ‘f’.
| C.I. | 0 – 10 | 10 – 20 | 20 – 30 | 30 – 40 | 40 – 50 |
| Frequency | 8 | 22 | 31 | f | 2 |
उत्तर
`barx = 21 1/7 = 148/7`
| C.I. | Frequency | Mid-value (xi) | fixi |
| 0 – 10 | 8 | 5 | 40 |
| 10 – 20 | 22 | 15 | 330 |
| 20 – 30 | 31 | 25 | 775 |
| 30 – 40 | f | 35 | 35f |
| 40 – 50 | 2 | 45 | 90 |
| Total | 63 + f | 1235 + 35f |
`barx = (sumf_ix_i)/(sumf_i) = (1235 + 35f)/(63 + f)`
`=> 148/7 = (1235 + 35f)/(63 + f)`
`=> 9324 + 148f = 8645 + 245f`
`=> 245f - 148f = 9324 - 8645`
`=> f = 679/97 `
`=>` f = 7
APPEARS IN
संबंधित प्रश्न
Find the mean of the following set of numbers:
11, 14, 23, 26, 10, 12, 18 and 6
The following table shows the frequency distribution of heights of 51 boys:
| Height (cm) | 120 | 121 | 122 | 123 | 124 |
| Frequency | 5 | 8 | 18 | 10 | 9 |
Find the mode of heights.
Find the mean of the following frequency distribution by the step deviation method :
| Class | 100-110 | 110-120 | 120-130 | 130-140 | 140-150 |
| Frequency | 15 | 18 | 32 | 25 | 10 |
Find the median of:
241, 243, 347, 350, 327, 299, 261, 292, 271, 258 and 257
Find the mean of 53, 61, 60, 67 and 64.
Find the mean of first five prime numbers.
Find the mean of squares of first five whole numbers.
Find the mean and the median of: 0.5, 5.6, 3.8, 4.9, 2.7 and 4.4
If the median of a, 2a, 4a, 6a, 9a is 8, then find the value of a is
The marks scored by the students in social test out of 20 marks are as follows: 12, 10, 8, 18, 14, 16. Find the mean and median?
