A)
1)1/5 + 1/3 = 3/15 + 5/15 = 8/15
2) 8/15 : 4 = 8/15 * 1/4 = 2/15
б)
1) 1 - 7/12 = 5/12
2) 5/12 : 10 = 5/12 * 1/10 = 1/24
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a)
1) 1 + 1/2 = 1 1/2 = 3/2
2) 1 : 3/2 = 1 * 2/3 = 2/3
б)
1) 1 + 4/5 = 1 4/5 = 9/5
2) 1 : 9/5 = 1 * 5/9 = 5/9