The average height of 35 boys in a class was calculated as 180cm. It has later found that the height of one of the boys in the class was wrongly written as 166 cm whereas his actual height was 106 cm. Find the actual average height of the boys in the class (Round off your answer to two decimal places)?

A. 179.29 cm
B. 178.29 cm
C. 179.38 cm
D. 178.39 cm

Explanation:

Calculated average height of 35 boys = 180 cm.

Wrong total height of 35 boys = 180 * 35 cm. This was as a result of an actual height of 106 cm being wrongly written as 166 cm. Correct total height of 35 boys = 180 * 35 cm – 166 cm + 106 cm
= 180 * 35 cm – 166 cm + 106 cm/35 = 180 cm – 60 /35 cm
= 180 cm – 1.71 cm = 178.29 cm