Răspuns:
Explicație pas cu pas:
11
5/4 + 3/4 = 8/4 = 2
1/2 + 3/4 = 2/4 + 3/4 = 5/4
1/6 + 3/4 = 2/12 + 9/12 = 11/12
7/8 + 3/4 = 7/8 + 6/8 = 13/8
5/12 + 3/4 = 5/12 + 9/12 = 14/12 = 7/6
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12
3/4 + 1/6 = 9/12 + 2/12 = 11/12
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13
1/3 + 1/4 + 1/5 = 20/60 + 15/60 + 12/60 = 47/60
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14
a + b = 15
a*b = 56
(a + b)/a*b = 15/56
1/b + 1/a = 15/56
