I am the product of two prime numbers, both less than ten. My square root is an integer. What am I?

Category: Math · Difficulty: hard

Hint: Focus on prime factors to solve this.

Answer

Fifteen

Explanation

Fifteen equals three times five, both prime numbers under ten, and has a square root of 3.87.

This is a hard math riddle — a tricky one that takes a little thought. The answer is Fifteen.

More Math riddles

All Math riddles · Riddles with answers · Home