Advertisements
Advertisements
प्रश्न
If the mean of the following data is 20.2, then find the value of p
| Marks | 10 | 15 | 20 | 25 | 30 |
| No. of students | 6 | 8 | p | 10 | 6 |
Advertisements
उत्तर
| Marks x |
No. of students f |
fx |
| 10 | 6 | 60 |
| 15 | 8 | 120 |
| 20 | p | 20p |
| 25 | 10 | 250 |
| 30 | 6 | 180 |
| `sumf` = 30 + p | `sumfx` = 610 + 20p |
`bar(x) = (sumfx)/(sumf)`
20.2 = `(610 + 20"p")/(30 + "p")`
610 + 20 p = 20.2 ...(30 + p)
610 + 20 p = 606 + 20.2 p
610 – 606 = 20.2 p – 20 p
4 = 0.2 p
p = `4/0.2`
= `(4 xx 10)/2`
= 20
The value of p = 20
APPEARS IN
संबंधित प्रश्न
Find the mean of the first five whole numbers.
A cricketer scores the following runs in eight innings:
58, 76, 40, 35, 46, 45, 0, 100
Find the mean score.
The enrolment in a school during six consecutive years was as follows:
1555, 1670, 1750, 2013, 2540, 2820
Find the mean enrolment of the school for this period.
The calculated mean of 50 observations was 80. It was later discovered that observation 19 was recorded by mistake as 91. What was the correct mean?
Find the common difference of the A.P 3, 5, 7, ..........
In a research laboratory scientists treated 6 mice with lung cancer using natural medicine. Ten days later, they measured the volume of the tumor in each mouse and given the results in the table
| Mouse marking | 1 | 2 | 3 | 4 | 5 | 6 |
| Tumor Volume (mm3) | 145 | 148 | 142 | 141 | 139 | 140 |
Find the mean
The algebraic sum of the deviations of a set of n values from their mean is
The mean of a, b, c, d and e is 28. If the mean of a, c and e is 24, then mean of b and d is
The average of the marks 2, 9, 5, 4, 4, 8, 10 is ____________
The mean age of 25 teachers in a school is 40 years. A teacher retires at the age of 60 years and a new teacher is appointed in his place. If the mean age of the teachers in this school now is 39 years, then the age (in years) of the newly appointed teacher is ______.
