Question

The mean of 20 numbers is 43. If 6 is subtracted from each number . What will be the new mean.

Answer 1

Mean =(x1+x2------x20)/20


43={x1+x2-----x20}/20


43*20=860={x1+x2----x20)


If 6 is subtracted from 20 observations, it means that (20*6)is subtract from whole all observations


Mean ={(x1+x2-----x20)-120}/20


Mean =(860-120)/2


New mean =740/20

New mean = 37

Answer 2

The mean of 20 numbers is 43
The sum of all numbers will be 43×20
Sum is 860
So 6 is subtracted from each number
6×20=120
So....we have to Subtract 120 from 860
860-120
740
And we have to find the mean now
740/20
37
So the new mean is 37