Math & Logic · Ages 7–9
Riddle #69
Tom is 8 years old, and his little sister is half his age. How old will his sister be when Tom is 16?
You solved this one before
Answer: 12
His sister is 4 today, which makes her exactly 4 years younger than Tom — and she will be 4 years younger than him forever. So when Tom is 16 she is 12, not 8. She is "half his age" only today.