7stamba+5stofa=1622 /x2
4stamba+10stofa=1884
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14 stamba+10stofa=3244
4stamba+10stofa=2884
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10stamba // =1360
1 m stamba=1360:10
1 m stamba=136 lei
7x36+5stofa=1622
252+5stofa=1622
5stofa=1370
1 stofa=274 lei
proba: 7x36+5x274=252+1370=1622