Question 19
Gunmetal consists of 74% copper, 16% zinc and 10% tin and is made by mixing brass and bronze. Bronze consists of 80% copper, 4% zinc and 16% tin. Brass consists only of copper and zinc. If the ratio of copper to zinc in brass is $m:n$, where $m,n$ are relatively prime positive integers, find $m+n$.
Enter the number only.
Enter the number only.