Ответ:
Пошаговое объяснение:
11)
1) 2 1/4 : 1 4/11 = 9/4 : 15/11 = 9/4 * 11/15 = 33/20 = 1 13/20
2) 3/8 : 7/8 = 3/8 * 8/7 = 3/7
3) 1 13/20 - 3/7 = 1 91/140 - 60/140 = 1 31/140
ответ: 1 13/140
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12)
1) 5 1/6 : 4 2/15 = 31/6 : 62/15 = 31/6 * 15/62 = 5/4 = 1 1/4
2) 3 1/6 - 1 1/4 = 3 2/12 - 1 3/12 = 1 11/12
3) 1 11/12 * 3/92 = 23/12 * 3/92 = 1/16
ответ: 1/16