180m+70b=710 lei
60m+17b=205 lei /x3
---------------------------
180m+70b=710
180m+51b=615
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// 19b=95
1. Cat costa un kg de banane?
1 kg banane=95:19
1kg banane=5 lei
2).Cat costa un kg de mere?
180m+70x5=710
180m+350=710
180m=360
1 kg de mere=360:180
1kg mere=2 lei