3 ms·TIL: the mediant of two fractions a/b < (a+c)/(b+d) < c/dby ggeorgovassilis 4y agoTIL: the mediant of two fractions a/b < (a+c)/(b+d) < c/deps 4y agoEasy to prove too.GuB-42 4y agoJust found the proof, that's also how I noticed it doesn't work when one of the denominators is negative. If one of the denominators (not both) is negative, you are guaranteed to be outside of the range.