Jokes and Riddles

Math and Arithmetic

Algebra

# When does 9 plus 4 equal 1?

###### Wiki User

###### July 14, 2012 11:30PM

## 9 a.m + 4 hours = 1 p.m.

More generally, when you are doing modulus arithmetic, specifically mod 12.

ie.

(9+4) mod 12 = 1

not as tough as 9 pm + 4 hours = 1 am