Пошаговое объяснение:
1 пример:
1) 5. 1/4 - 4. 21/40 =
5. 10/40 - 4. 21/40 =
4. 50/40 - 4. 21/40 =
29/40
2) 29/40 : 1. 9/20 =
29/40 : 29/20 = 29/40 * 20/29 = 20/40 = 1/2
3) 7. 1/5 - 6. 7/8 =
7. 8/40 - 6. 35/40 =
6. 48/40 - 6. 35/40 =
13/40
4) 13/40 : 3/4 = 13/40 * 4/3 = 13/10 * 1/3 = 13/30
5) 1/2 - 13/30 = 15/30 - 13/30 = 2/30 = 1/15
ответ: 1/15
2 пример:
1) 3/4 : 5/6 = 3/4 * 6/5 =
18/20 = 9/10
2) 1 : 1. 1/9 = 1 : 10/9 =
1 * 9/10 = 9/10
3) 2. 1/2 * 2/5 = 5/2 * 2/5 = 1
4) 9/10 + 9/10 = 18/10 = 9/5 = 1. 4/5
5) 1. 4/5 - 1 = 4/5
ответ : 4/5
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