Răspuns:
Explicație pas cu pas:
9/5 + 4/10 = 9/5 + 2/5 = 11/5
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4/7 + 6/21 = 4/7 + 2/7 = 6/7
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21/18 + 28/24 = 7/6 + 7/6 = 14/6 = 7/3
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40/45 + 26/18 = 8/9 + 13/9 = 21/9 = 7/3
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33/24 + 21/56 = 11/8 + 3/8 = 14/8 = 7/4
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15/20 + 63/36 = 3/4 + 7/4 = 10/4 = 5/2
