2/7 привести к знаменателю 49, 5/13 к 78, 8/10 к 120, 7/33 к 99, 9/15 к 75, 11/12 к 144.

2/7 = 14/49 5/13 = 30/78 8/10 = 96/120 7/33 = 21/99 9/15 = 45/75 11/12 = 132/144