oops made the same mistake as poshen loh
so i learned that \(\phi(mn)=\phi(m)\cdot\phi(n)\) and i applied the fact on this problem and i got 4 😞
is the phi function only multiplicative (as in the above equation) when \(\gcd(m,n)=1?\)
Subcategories

Day 9
Repeating Patterns
Module 5 Day 9 Challenge Part 1Module 5 Day 9 Challenge Part 2Module 5 Day 9 Challenge Part 3Module 5 Day 9 Challenge Part 4Module 5 Day 9 Challenge Part 5Module 5 Day 9 Challenge Part 6Module 5 Day 9 Your Turn Part 1Module 5 Day 9 Your Turn Part 2Module 5 Day 9 Your Turn Part 3Module 5 Day 9 Your Turn Part 4 
Day 10
Chinese Remainder Theorem
Module 5 Day 10 Challenge Part 1Module 5 Day 10 Challenge Part 2Module 5 Day 10 Challenge Part 3Module 5 Day 10 Challenge Part 4Module 5 Day 10 Challenge Part 5Module 5 Day 10 Challenge Part 6Module 5 Day 10 Challenge Part 7Module 5 Day 10 Your Turn Part 1Module 5 Day 10 Your Turn Part 2Module 5 Day 10 Your Turn Part 3 
Day 12
More Remainders
Module 5 Day 12 Challenge Part 1Module 5 Day 12 Challenge Part 2Module 5 Day 12 Challenge Part 3Module 5 Day 12 Challenge Part 4Module 5 Day 12 Challenge Part 5Module 5 Day 12 Your Turn Part 1Module 5 Day 12 Your Turn Part 2Module 5 Day 12 Your Turn Part 3Module 5 Day 12 Your Turn Part 4Module 5 Day 12 Your Turn Part 5