### Brain Teasers

# Threes and Sevens

Using the four digits 3,3,7,7 and the mathematical operators +,-,*,/ write an expression equal to 24. You must use each digit exactly once, but may use each operator multiple times, or not at all. Parentheses are allowed. The following would be a valid expression:

(7 + 3)/(7 + 3) = 1

(7 + 3)/(7 + 3) = 1

### Hint

Think fractions.### Answer

(3 + 3/7) * 7 = 24Hide Hint Show Hint Hide Answer Show Answer

## What Next?

**Solve a Similar Brain Teaser...**

Or, get a random brain teaser.

If you become a registered user you can vote on this brain teaser, keep track of

which ones you have seen, and even make your own.

## Comments

Just for clarity, you don't need to use fractions since 7 divided by four gives you the same answer as the fraction 7/4. Very good problem!

Feb 12, 2002

or you could try:

(7*3)+(7-3)=24

(7*3)+(7-3)=24

Very good problem. I'm sorry Elsie, your answer adds up to 25.

elsie, that's 25

This is one of the best teasers I've seen!

## Follow Braingle!