Răspuns:
Explicație pas cu pas:
b) raportul lor este 3/7
iar 2a + b = 180
a/b = 3/7
a = 3b/7
2*3b/7 + b = 180
6b/7 + b = 180
6b/7 + 7b/7 = 180
13b/7 = 180
b = 7*180/13 = 1260/13
a = 3/7*1260/13 = 540/13
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c) a/3 = b/11 iar b - a = 64
11a = 3b
3b - 3a = 192
11a - 3a = 192
8a = 192
a = 192 : 8 = 24
b = 64 + a = 64 + 24 = 88
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d) a/5 = 2b/3 iar a + 3b = 38
a = 10b/3
10b/3 + 3b = 38
10b/3 + 9b/3 = 38
19b/3 = 38
b = 38 : 19/3 = 38*3/19 = 6
a = 10*6/3 = 20