Răspuns:
35.
(3a+2b)/24 = 18 rest 16
3a+2b=18×24+16
3a+2b=448
(3a-2b)/(a-2b)=5
3a-2b=5a-10b=>8b=2a=>a=4b
3×4b+2b=448
14b=448
b=32
a=4×32=>a=128
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36.
b+f=32=>b=32-f
b+5=2(f-7)=>b+5=2f-14
32-f+5=2f-14
37+14=2f+f
51=3f=>f=51:3=>f=17 fete
b=32-17=>b=15 baieti
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37.
80%.....................307,2 lei
100%..............................x
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x=100×307,2:80=384 lei
120%.................384 lei
100%...........................x
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x=100×384:120=320 lei pretul initial
