Question

If the standard deviation of x, y, z is p then the standard deviation of 3x + 5, 3y + 5, 3z + 5 is 

Options

• 3p + 5

• 3p

• p + 5

• 9p + 15

Answer 1

3p

Explanation;

Hint:

(i) Each value is added by any constant there is no change in standard deviation.

(ii) Each value is multiplied by 3 standard deviations also multiplied by 3.

The standard deviation is 3p.