Question

Calculate the number of integers from 1 to 180 that are co-prime to 180. Then calculate 7^98mod180. I have answers for this but I'm unsure whether they are correct.

Answer 1

So you have two questions that's right?

Answer 2

yes but i think the first helps answer the second perhaps?

Answer 3

For the first one \( φ(180) =\color{red}{ 48} \) and for the second one use Fermat Euler theorem \[ 7^{98} \equiv 7^2 \equiv \color{red}{ 49} \pmod {180} \]

Answers are in color red.

Answer 4

Yes brilliant thank you so much! :)