The Mean & S.D of a distribution are 15 & 2 respectively. Find Mean &S.D if the obsn are multiplied by 5.?

Question

The Mean & S.D of a distribution are 15 & 2 respectively. Find Mean &S.D if the obsn are multiplied by 5

Answer 1

Here's a couple rules:

If you *add* a constant to the observed values, the mean will increase by the same amount, but the standard deviation will not change.

If you *multiply* the observed values by a constant, the mean  *and* the standard deviation will be multiplied by that same amount.

Answer:

New mean = 75

New S.D. = 10

Answer 2

Mean and SD are also 5 times bigger: 75 and 10