5l+5n+8f=54 lei -
3l+1n+7f=35 lei
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2l+4n+1f=19 lei
2l+4n+2f=22 lei -
2l+4n+1f=19 lei
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0+0+1f=3 lei
1f=3 lei
3l+1n+7f=35 lei
3l+1n+7×3=35
3l+1n=35-21
3l+1n=14
1n=14-3l
2l+4n+2f=22 lei
2l+4(14-3l)+2×3=22
2l+56-12l+6=22
56+6-22=12l-2l
10l=40
l=40÷10
l=4 lei
n=14-3×4
n=14-12
n=2 lei