Question

The Jones family has 3 children.

Answer 1

Amy = x
Betty = y
Carl = z
x + y = 29
x + z = 27
y + z = 22
y = 29 - x
z = 27 - x
29 - x + 27 - x = 22
-2x + 56 = 22
-2x = - 34
x = 17
y = 12
z = 10
Oldest child is Amy (17) and youngest child is Carl (10)
17 - 10 = 7
The difference between oldest child and youngest child is 7 years.