feb long challenge guess it right problem

challenge
feb
guess
it
long
right

#1

In the problem statement it is given than P/Q, where P and Q are coprime positive integers. You should compute P⋅Q−1 modulo 10^9+7, where Q−1 denotes the multiplicative inverse of Q modulo 10^9+7.
But then how can for 1/5 the answer becomes 400000003.


#2

See this https://discuss.codechef.com/questions/145069/guessrt-feb19b


#3

multiplicative inverse of 5 modulo 10^9+7 is 400000003