Question

The masses of five marbles are 50 g, 55 g, 60 g, 65 g and 70 g. Find their average mass.

Answer 1

The sum of masses of all marbles

= 50 g + 55 g + 60 g + 65 g + 70 g = 300 g

Number of marbles = 5

Average mass of a marble = sum of mass / no. of marbles

= 300 / 5 g 

= 60 g