Вычислите: а) 5/18 + 5/18; б) 6/5 - 5/6; в) 7/25 + 4/5; г) 11/48 + 11/64.

а) 5/18 + 5/18 = 10/18 = 5/9; б) 6/5 - 5/6 = 36/30 - 25/30 = 11/30; в) 7/25 + 4/5 = 7/25 + 20/25 = 27/25; г) 11/48 + 11/64 = 176/768 + 132/768 = 308/768 = 11/28.