Question: John had a son James when he was 19.  James is now twice as old as his sister Dora, who will turn 12 in 3 years.  How old will John's youngest son, who was born when John was 32, be in 3 years?
Give me a solution to this problem
Answer: 
Dora is 12-3=9
So James is 9*2=18 years old
That means John is 18+19=37
Johns youngest son is 37-32=5 years old
So he will be 5+3=8 in 3 years