Four children made the following statements.
Rebecca : The average of Christopher's mass and my mass is 32 kg.
Andrew : I am the heaviest.
Christopher : Claire is 2 kg lighter than Andrew.
Claire : Our masses are in consecutive order.

What is the total mass of Rebecca, Andrew and Christopher ?
Order of the mass of 4 children:
_____ , Claire, _____ , Andrew (Heaviest)

Total mass of Rebecca and Christopher 
= 2 x 32
= 64 kg

For Rebecca and Christopher,
Mass of the lighter one = 1 u
Mass of the heavier one = 1 u + 2

Total mass of Rebecca and Christopher
= 1 u + 1 u + 2
= 2 u + 2

2 u + 2 = 64 
2 u = 64 - 2
2 u = 62

1 u = 62 ÷ 2 = 31

The mass of the four children in consecutive order is 31, 32, 33 and 34.

Total mass of Rebecca, Andrew and Christopher
= 31 + 33 + 34
= 98

Answer(s): 98 kg