Question

Find the mean of 5, 6,17, 8, 9, 15, 23,18,10 & 24. Also find

the resulting mean, If each observation decreased by 2.​

Answer 1

Answer :-

$\sf Mean = \dfrac{Sum \: of \: observations}{Number \: of \: observations}$

$\sf = \dfrac{5 + 6 + 17 + 8 + 9 + 15 + 23 + 18 + 10 + 24}{10}$

$\sf = \dfrac{135}{10}$

$\sf = \boxed{\sf 13.5}$

When the terms are reduced by 2 -

$\sf Mean = \dfrac{5 + 6 + 17 + 8 + 9 + 15 + 23 + 18 + 10 + 24 - 2 - 2 - 2 - 2 -2-2-2-2-2-2}{10}$

$\sf = \dfrac{135 - 20}{10}$

$\sf = \dfrac{115}{10}$

$= \boxed{\sf 11.5}$