2023 Fermat Problem 11

At the start of this month, Mathilde and Salah each had 100 coins. For Mathilde, this was 25\% more coins than she had at the start of last month. For Salah, this was 20\% fewer coins than he had at the start of last month. The total number of coins that they had at the start of last month was

\textbf{(A)}\ 180\quad \textbf{(B)}\ 185\quad \textbf{(C)}\ 190\quad \textbf{(D)}\ 200\quad \textbf{(E)}\ 205

If there are no answer choices shown, enter a numerical answer.

Full credit to this problem is given to the CEMC, you may view all Fermat contests here.