## Editorial for A Fraction Problem

Remember to use this editorial only when stuck, and not to copy-paste code from it. Please be respectful to the problem author and editorialist.

Submitting an official solution before solving the problem yourself is a bannable offence.

Author:

One possible answer would be $$e = a+c$$ and $$f = b+d$$.

The proof is left as an exercise for the reader. Hint, solve this inequality by expanding everything:

$\frac{a}{b} < \frac{a+c}{b+d} < \frac{c}{d}$