# Math Help - mod not explained

1. ## mod not explained

what is 3 to the power -1 (mod 29)?

2. Originally Posted by idontdomath
what is 3 to the power -1 (mod 29)?
You can think of modular arithmetic as clock arithmetic, so a number ${\rm{modulo}}~
29$
is the remainder when that number is divided by 29.

In this case we are looking for a number $N$ in $[0,28]$ such that:

$3N=29 \times k +1$

for some integer $k$

RonL

3. Originally Posted by CaptainBlack
You can think of modular arithmetic as clock arithmetic, so a number ${\rm{modulo}}~
29$
is the remainder when that number is divided by 29.

In this case we are looking for a number $N$ in $[0,28]$ such that:

$3N=29 \times k +1$

for some integer $k$

RonL
That makes a lot more sense than what I was thinking (glad I kept my mouth shut ^_^)