Advertisements
Advertisements
प्रश्न
If the mean of the following data is 20.2, find the value of p:
| x | 10 | 15 | 20 | 25 | 30 |
| f | 6 | 8 | p | 10 | 6 |
उत्तर
We know that,
Mean of the data `(barx) = (sum_(i = 1)^5 f_i x_i)/(sum_(i = 1)^5 f_i) = 20.2` ...[Given]
⇒ `(f_1x_1 + f_2x_2 + f_3x_3 + f_4x_4 + f_5x_5)/(f_1 + f_2 + f_3 + f_4 + f_5) = 20.2`
⇒ `((6)(10) + (8)(15) + (p)(20) + (10)(25) + (6)(30))/(6 + 8 + p + 10 + 6) = 20.2`
⇒ `(60 + 120 + 20p + 250 + 180)/(30 + p) = 20.2`
⇒ 20p + 610 = 606 + 20.2p
⇒ 610 – 606 = 0.2p
⇒ `(2p)/10 = 4`
∴ p = 10 × 2 = 20
Hence, the value of p is 20.
APPEARS IN
संबंधित प्रश्न
In a mathematics test given to 15 students, the following marks (out of 100) are recorded:-
41, 39, 48, 52, 46, 62, 54, 40, 96, 52, 98, 40, 42, 52, 60
Find the mean, median and mode of this data.
The percentage of marks obtained by students of a class in mathematics are : 64, 36, 47, 23,
0, 19, 81, 93, 72, 35, 3, 1. Find their mean.
The mean of marks scored by 100 students was found to be 40. Later on it was discovered
that a score of 53 was misread as 83. Find the correct mean.
The mean of 5 numbers is 18. If one number is excluded, their mean is 16. Find the excluded number.
Find the value of p for the following distribution whose mean is 16.6
| x: | 8 | 12 | 15 | p | 20 | 25 | 30 |
| f : | 12 | 16 | 20 | 24 | 16 | 8 | 4 |
Find the missing value of p for the following distribution whose mean is 12.58.
| x | 5 | 8 | 10 | 12 | p | 20 | 25 |
| f | 2 | 5 | 8 | 22 | 7 | 4 | 2 |
Find the mode of the following data :
7, 9, 12, 13, 7, 12, 15, 7, 12, 7, 25, 18, 7
If the median of scores \[\frac{x}{2}, \frac{x}{3}, \frac{x}{4}, \frac{x}{5}\] and \[\frac{x}{6}\] (where x > 0) is 6, then find the value of \[\frac{x}{6}\] .
Mode is
There are 10 observations arranged in ascending order as given below. 45, 47, 50, 52, x, x + 2, 60, 62, 63, 74. The median of these observations is 53. Find the value of x. Also find the mean and the mode of the data.
