Question

calculați exercițiile a)5/12-3/14+2/7;b)9/20+7/10-2/5;c)11/20-(1/4+1/5);va rog frumos
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Answer 1

Răspuns:

a) 5/12 - 3/14 + 2/7 =

= 70/168 - 36/168 + 2/7 =

= 34/168 + 2/7 =

= 34/168 + 48/168 =

= 82/168 (simplificăm cu 2) = 41/84

b) 9/20 + 7/10 - 2/5 =

= 9/20 + 14/20 - 2/5 =

= 23/20 - 2/5 =

= 23/20 - 8/20 =

= 15/20 (simplificăm cu 5) = 3/4

c) 11/20 - (1/4 + 1/5) =

= 11/20 - (5/20 + 4/20) =

= 11/20 - 9/20 =

= 2/20 (simplificăm cu 2) = 1/10