Four children made the following statements.
Aaron : The average of Andrew's mass and my mass is 27 kg.
Sophia : I am the heaviest.
Andrew : Lily is 2 kg lighter than Sophia.
Lily : Our masses are in consecutive order.

What is the total mass of Aaron, Sophia and Andrew ?
Order of the mass of 4 children:
_____ , Lily, _____ , Sophia (Heaviest)

Total mass of Aaron and Andrew 
= 2 x 27
= 54 kg

For Aaron and Andrew,
Mass of the lighter one = 1 u
Mass of the heavier one = 1 u + 2

Total mass of Aaron and Andrew
= 1 u + 1 u + 2
= 2 u + 2

2 u + 2 = 54 
2 u = 54 - 2
2 u = 52

1 u = 52 ÷ 2 = 26

The mass of the four children in consecutive order is 26, 27, 28 and 29.

Total mass of Aaron, Sophia and Andrew
= 26 + 28 + 29
= 83

Answer(s): 83 kg