Приведите к наименьшему общему знаменателю дроби: а) 1/8 и 3/4 9/10 и 1/20 2/3 и 7/12 7/15 и 3/5 б) 1/2 и 1/3 2/5 и 3/4 3/16 и 2/3 1/4 и 9/25 в) 7/15 и 5/9 1/6 и 3/10 5/12 и 7/15 7/20 и 7/8

а) 1/8 и 3/4 = (3 * 2) / (4 * 2) = 6/8; 9/10 = (9 * 2) / (10 * 2) = 18/20 и 1/20; 2/3 = (2 * 4) / (3 * 4) = 8/12 и 7/12; 7/15 и 3/5 = (3 * 3) / (5 * 3) = 9/15; б) 1/2 = (1 * 3) / (2 * 3) = 3/6 и 1/3 = (1 * 2) / (3 * 2) = 2/6; 2/5 = (2 * 4) / (5 * 4) = 8/20 и 3/4 = (3 * 5) / (4 * 5) = 15/20; 3/16 = (3 * 3) / (16 * 3) = 9/48 и 2/3 = (2 * 16) / (3 * 16) = 32/38; 1/4 = (1 * 25) / (4 * 25) = 25/100 и 9/25 = (9 * 4) / (25 * 4) = 36/100; в) 7/15 = (7 * 3) / (15 * 3) = 21/45 и 5/9 = (5 * 5) / (9 * 5) = 25/45; 1/6 = 5/30 и 3/10 = 9/30; 5/12 = 25/60 и 7/15 = 28/60; 7/20 = 14/40 и 7/8 = 35/40.