I am a prime number.
The double of myself is equal to the square of me.

which number am I?

Replace the (?) with the correct mathematical signs to make the expression equal to 59.

18 ? 12 ? 4 ? 5 = 59

A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

How many triangles are there on the puzzle below?

James ordered a fishing rod, priced at $3.56. Unfortunately, James is an Eskimo who lives in a very remote part of Greenland and the import rules forbid any package longer than 4 feet to be imported. The fishing rod was 4 feet and 1 inch, just a little too long, so how can the fishing rod be mailed to James without breaking the rules? Ideally James would like the fishing rod to arrive in one piece!

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

Find three numbers such that When we multiply three numbers, we will get the prime numbers. The difference between the second and the first number is equal to the third and second.

What's a single-digit number with no value?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?