This family riddle sounds like a multiplication problem, but the wording is the real trick.
A man has 3 sons, and each son has 2 sisters.
The key is that the sons can all share the same two sisters. The riddle never says each son has two different sisters.
That means the family has:
3 sons + 2 daughters = 5 children
So the correct answer is 5.
A common mistake is counting two sisters for each son and getting 9 children. But siblings in the same family can share the same sisters.
Answer: 5 children.
This is a classic example of a riddle that rewards careful reading more than fast arithmetic.
