Question

The mean of eight numbers is 65. If 3 is added to each number, then find the new mean

Answer 1

let the 8 numbers be a,b,c...h

according to given question

a+b+c+....h/8=65
a+b+c...+h=520

now 3 is added to each no.

(a+3)+(b+3)+(c+3).....+(h+3)/8=X

(a+b+c...+h)+24/8=X

520+24/8=X

X=544/8

X=68

Answer 2

Hey dear...

The answer is...

Mean = 65

There are 8 numbers.

3 will be added to every number.

Then....

8× 3= 24

Mean = sum of the observation/ total number if observation.

Before the sum of the total observation must be....

= 65 × 8 = 520
= 520 was the total observation.
= Now it would be...
= 520+24= 544

So the mean is...

= 544/ 8 = 68

Hence the new mean is 68.

Hope this helps. Thank you.