Răspuns:
Explicație:
21/35 = 3/5
____________
6/12 = 13/26
12/6 = 26/13
6/13 = 12/26
13/6 = 26/12
______________
x/25 = 4/10
x = 25*4/10 = 100/10 = 10
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40 = 5/x
x = 5/40 = 1/8
________________
a + b = 168
a/5 = b/3 = k
a = 5k
b = 3k
5k + 3k = 168
8k = 168
k = 168 : 8 = 21
a = 5*21 = 105
b = 3*21 = 63
