Advertisements
Advertisements
प्रश्न
The mean of x, x + 2, x + 4, x + 6 and x + 8 is 11, find the mean of the first three observations.
Advertisements
उत्तर
Let `barx` be the mean of n number of observation x1, x2, x3, ...., xn.
Mean = `[ x_1 + x_2 + x_3 + ......... + x_n ]/n`
Therefore,
Mean of given data
= `[ x + x + 2 + x + 4 + x + 6 + x + 8 ]/5`
= `[ 5x + 20 ]/5`
= x + 4
Also, it's given that mean of the given data is 11.
⇒ x + 4 = 11
⇒ x = 7
Hence the mean of the first three observation = `[ x + x + 2 + x + 4 ]/3`
= `[3x + 6]/3`
= x + 2
= 7 + 2
= 9.
APPEARS IN
संबंधित प्रश्न
The mean of 15 observations is 32. Find the resulting mean, if the observation is: Decreased by 20%
Find the mean of 8, 12, 16, 22, 10 and 4. Find the resulting mean, if the observations, given above, be: multiplied by 3 and then divided by 2.
Find the mean of 8, 12, 16, 22, 10 and 4. Find the resulting mean, if each of the observations, given above, be: increased by 25%
The average of n numbers x1, x2, x3 ….. xn is A. If x1 is replaced by ( x+ α )x1, x2, is replaced by ( x+ α )x2 and so on.
Find the new average.
The weight of the seven members of a family, in kilograms are given below:
20, 52, 56, 72, 64, 13, 80.
Find mean weight.
The marks obtained by 10 students are listed below:
2, 5, 3, 8, 0, 9, x, 6, 1, 8
If the mean marks is 5, find x.
A test out of 25 marks was given to 16 students and marks scored are recorded below:
25, 8, 14, 20, 16, 22, 10, 15, 8, 7, 24, 18, 19, 6, 11, 14
Find the mean marks
The mean of 16 natural numbers is 48. Find the resulting mean, if each of the number is multiplied by 4
The mean of 16 natural numbers is 48. Find the resulting mean, if each of the number is increased by 50%
The mean monthly income of 8 men is Rs. 8079.75. A man whose monthly income is Rs. 8280 has also been taken into consideration. Calculate the mean monthly income of all the men.
