a : 2 + a : 4 = 141
a/2 + a/4 = 141
aducem la acelasi numitor si vom avea:
2a + a = 141 x 4
3a = 564
a = 188
proba
188/2+ 188/4 = 94+47 = 141
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sau
notam a : 2 = b,
a : 4 = 2b
b + 2b = 141
3b = 141
b= 141: 3
b= 47
a :2 = 47
a: 4 = 2 x 47
a : 4 = 94
proba: 47 + 94 = 141