Ответ:
Пошаговое объяснение:
1) 7/12 * 1 19/21 = 7/12 * 40/21 = 10/9 = 1 1/9
2) 17/72 * 2/3 = 17/108
3) 18 5/12 - 1 1/9 = 18 15/36 - 1 4/36 = 17 11/36
4) 17 11/36 - 17/108 = 17 33/108 - 17/108 = 17 16/108 = 17 4/27
ответ: 17 4/27
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1) 9 1/4 * 8 = 37/4 * 8 = 74
2) 1 2/3 * 5 1/2 = 5/3 * 11/2 = 55/6 = 9 1/6
3) 4 2/5 * 4 7/12 = 22/5 * 55/12 = 121/6 = 20 1/6
4) 9 1/6 + 20 1/6 = 29 2/6 = 29 1/3
5) 74 - 29 1/3 = 44 2/3
ответ: 44 2/3
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