Răspuns:
Explicație pas cu pas:
6/5 - n/5 + 1/5 = 5/5
6/5 - n/5 = 5/5 - 1/5 = 4/5
n/5 = 6/5 - 4/5 = 2/5
n = 2
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n/7 + 2/7 - 6/7 = 7/7
n/7 + 2/7 = 7/7 + 6/7 = 13/7
n/7 = 13/7 - 2/7 = 11/7
n = 11
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9/10 - 2/10 + n/10 = 10/10
7/10 + n/10 = 10/10
n/10 = 10/10 - 7/10 = 3/10
n = 3
