Advertisements
Advertisements
प्रश्न
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.
उत्तर
Mean of n numbers = A
⇒ A = `[ x_1 + x_2 + ...... + x_n ]/n`
⇒ x1 + x2 + ............. + xn = n x A ......(i)
New Mean
= `[( x + a )x_1 + ( x + a )x_2 + ....... + ( x + a )x_n ]/n`
= `[ ( x + a )( x_1 + x_2 + .......... + x_n )]/n`
= `[ ( x + a )( n xx "A")]/n` .....[ From(i) ]
= `[( x + a ) xx n xx "A" ]/n`
= ( x + a )A
APPEARS IN
संबंधित प्रश्न
The mean of 15 observations is 32. Find the resulting mean, if the observation is: Increased by 60%
Find the mean of 8, 12, 16, 22, 10 and 4. Find the resulting mean, if the observations, given above, be: multiplied by 3.
The mean of x, x + 2, x + 4, x + 6 and x + 8 is 11, find the mean of the first three observations.
For the set of numbers given below, find mean: 3, 0, 5, 2, 6, 2
Individual scores of a school cricket eleven in a match are given below:
10, 9, 31, 45, 0, 4, 8, 15, 12, 0, 6
Find the average score.
The mean of 16 natural numbers is 48. Find the resulting mean, if each of the number is increased by 5
The mean of 16 natural numbers is 48. Find the resulting mean, if each of the number is increased by 50%
The mean of 16 natural numbers is 48. Find the resulting mean, if each of the number is decreased by 10%
The mean of 4 observations is 20. If one observation is excluded, the mean of the remaining observations becomes 15. Find the excluded observation.
A boy scored the following marks in various class tests during a term, each test being marked out of 20.
15, 17, 16, 7, 10, 12, 14, 16, 19, 12, 16
What is his mean marks?
