Question

The mean of five ovservation is X. If 4 is added to each ovservation, find the new mean?​

Answer 1

Answer:

let the first observation a

second observation b

third observation c

fourth observation d

fifth observation e

a+b+c+d+e/5=X

4 is added in each observation .

So,

4a+4b+4c+4d+4e/5

4(a+b+c+d+e)/5

4(4)/5

16/5 is the new mean

Answer 2

GIVEN

The Mean of five Observation is X

Again 4 is added to each observation

TO FIND

The New Mean

SOLUTION

Let the Observations be A1, A2, A3, A4 and A5

We have,

(A1 + A2 + A3 + A4 + A5)/5 = X

=> A1 + A2 + A3 + A4 + A5 = 5X ... eq.01

Again 4 is added to each observation :-

New Mean will be,

{(A1 + 4)+(A2 + 4)+(A3 + 4)+(A4 + 4)+(A5 + 4)}/5

= [(A1 + A2 + A3 + A4 + A5) + (4+4+4+4+4)]/5

= (5X + 20)/5

= {5(X + 4)}/5

= X + 4

Hence the new Mean is x + 4 (ANS)