Question

I have two story problems.

Answer 1

Let lucy = l & neighbour= n
l = n +4
l + n= 14 years
substitute l with n +4
(n +4) + n = 14
2n +4 =14
n=5 years
l = n + 4 lets substitute n with 5
l = 5 + 4
lucy = 9 years