3)
1) 12 5/12 + 1 2/3 = 12 5/12 + 1 8/12 = 13 13/12
2) 13 13/12 - 3 5/6 = 13 13/12 - 3 10/12 = 10 3/12 = 10 1/4
3) 10 1/4 + 2 3/4 = 12 4/4 = 13
4) 2 1/2 * 2/5 = 5/2 * 2/5 = 1
5) 1 - 7/9 = 2/9
6) 13 : 2/9 = 13 * 9/2 = 117/2 = 58 1/2
ответ: 58 1/2
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4)
1)1 1/2 * 1/3 = 3/2 * 1/3 = 1/2
2) 13 : 26 = 13/26 = 1/2
3) 1/2 - 1/2 = 0
4) 48 3/5 : 6 3/4 = 243/5 : 27/4 = 243/5 * 4/27 = 36/5
5) 36/5 * 5/12 = 3
6) 1 75/94 * 0 = 0
7) 3 - 2 5/6 = 1/6
8) 1/6 + 0 = 1/6
ответ: 1/6