Решение:
- а) 3/7 · 5/11 = (3 * 5) / (7 * 11) = 15/77
- б) 6/25 · 5/18 = (6 * 5) / (25 * 18) = 30 / 450 = 1/15
- в) 4/7 : 2 = 4/7 * 1/2 = 4/14 = 2/7
- г) 5/9 : 10/27 = 5/9 * 27/10 = (5 * 27) / (9 * 10) = 135 / 90 = 3/2
- д) 12/13 : 6 = 12/13 * 1/6 = 12 / (13 * 6) = 12 / 78 = 2/13
- е) 4 : 6/13 = 4 * 13/6 = 52/6 = 26/3
Финальный ответ:
а) 15/77; б) 1/15; в) 2/7; г) 3/2; д) 2/13; е) 26/3