Four children made the following statements.
Jonathan : The average of Josiah's mass and my mass is 33 kg.
Ellie : I am the heaviest.
Josiah : Matthew is 2 kg lighter than Ellie.
Matthew : Our masses are in consecutive order.

What is the total mass of Jonathan, Ellie and Josiah ?
Order of the mass of 4 children:
_____ , Matthew, _____ , Ellie (Heaviest)

Total mass of Jonathan and Josiah 
= 2 x 33
= 66 kg

For Jonathan and Josiah,
Mass of the lighter one = 1 u
Mass of the heavier one = 1 u + 2

Total mass of Jonathan and Josiah
= 1 u + 1 u + 2
= 2 u + 2

2 u + 2 = 66 
2 u = 66 - 2
2 u = 64

1 u = 64 ÷ 2 = 32

The mass of the four children in consecutive order is 32, 33, 34 and 35.

Total mass of Jonathan, Ellie and Josiah
= 32 + 34 + 35
= 101

Answer(s): 101 kg