Advertisements
Advertisements
प्रश्न
Following 10 observations are arranged in ascending order as follows.
2, 3, 5, 9, x + 1, x + 3, 14, 16, 19, 20
If the median of the data is 11, find the value of x.
उत्तर
Observations are arranged in ascending order as follows:
2, 3, 5, 9, x + 1, x + 3, 14, 16, 19, 20
As, the number of observations = 10, which is an even number.
∴ The numbers in the five and six observations will come to the middle.
Median = 11
∴ मध्यक = `((x + 1) + (x + 3))/2`
∴ 11 = `(2x + 4)/2`
∴ 11 × 2 = 2x + 4
∴ 22 = 2x + 4
∴ 22 − 4 = 2x
∴ 2x = 18
∴ x = `18/2`
∴ x = 9
So, the value of x is 9.
APPEARS IN
संबंधित प्रश्न
The marks of 10 students of a class in an examination arranged in ascending order is as follows:
13, 35, 43, 46, x, x + 4, 55, 61, 71, 80
If the median marks is 48, find the value of x. Hence, find the mode of the given data.
If each number given in (a) is diminished by 2, find the new value of mean.
If 69.5 is the mean of 72, 70, ‘x’, 62, 50, 71, 90, 64, 58 and 82, find the value of ‘x’.
The daily wages of 80 workers in a building project are given below :
| Wages (Rs) | No.of workers |
| 30-40 | 6 |
| 40-50 | 10 |
| 50-60 | 15 |
| 60-70 | 19 |
| 70-80 | 12 |
| 80-90 | 8 |
| 90-100 | 6 |
| 100-110 | 4 |
Using graph paper, draw an ogive for the above distribution. Use your ogive, to estimate :
(1) the mediam wages of workers
(2) the percentage of workers who earn more than Rs 75 a day.
(3) the upper quartile wages of the workers
(4) the lower quartile wages of the workers
(5) Inter quartile range
If the mean of 8 , 14 , 20 , x and 12 is 13, find x.
Find the mode of the following:
6, 7, 1, 8,6,5, 9, 4, 6, 7, 1,3, 2, 6, 7,8
Find the mode of the following:
15, 17, 16, 17, 10, 12, 14, 16, 19, 12, 16, 15, 16
Find the median of the following frequency distribution :
| Weight(kg) | 36 | 38 | 40 | 42 | 44 |
| No. of students | 11 | 26 | 29 | 24 | 10 |
The marks of 200 students in a test is given below :
| Marks% | 10-19 | 20-29 | 30-39 | 40-49 | 50-59 | 60-69 | 70-79 | 80-89 |
| No. of Students | 7 | 11 | 20 | 46 | 57 | 37 | 15 | 7 |
Draw an ogive and find
(i) the median
(ii) the number of students who scored more than 35% marks
Find the mean of: 2.1, 4.5, 5.2, 7.1 and 9.3
