Question

6 mingi si 6 masinute costa 3000 de lei.
4 mingi si 3 masinute costa 1700 lei.
Cat costa o minge?

Answer 1

6 mingi..........6 masinute..........3000 lei

4 mingi..........3 masinute...........1700 lei   /x2

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6 mingi..........6 masinute..........3000 lei

8 mingi..........6 masinute..........3400 lei

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2 mingi              //                    400lei

1 minge=400:2

1 minge=200 lei