Four children made the following statements.
Ryan : Joshua is 2 kg heavier than Sofia.
Sofia : Our masses are in consecutive order.
Elijah : The average of Ryan's mass and my mass is 25 kg.
Joshua : I am the heaviest.

What is the total mass of Elijah, Joshua and Ryan ?
Order of the mass of 4 children:
_____ , Sofia, _____ , Joshua (Heaviest)

Total mass of Elijah and Ryan
= 2 x 25
= 50 kg

For Elijah and Ryan,
Mass of the lighter one = 1 u
Mass of the heavier one = 1 u + 2

Total mass of Elijah and Ryan
= 1 u + 1 u + 2
= 2 u + 2

2 u + 2 = 50
2 u = 50 - 2
2 u = 48

1 u = 48 ÷ 2 = 24

The mass of the four children in consecutive order is 24, 25, 26 and 27.

Total mass of Elijah, Joshua and Ryan
= 24 + 26 + 27
= 77

Answer(s): 77 kg