Notam:
p=pixuri
c=creioane
3p si 2c=290g
2p si 3c =285 g
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pix=?g
creion=?g
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2c+ 3p+ 2p+ 3c=290g+ 285g
5c+ 5p= 575g
5*(c+p)=575
c+p= 575:5
c+p=115
3p+ 2c= 290g
p+230g=290g
p=290g-230g
p=60g
3*p + 2*c= 290g
3*60g + 2*c= 290g
180g+2*c= 290g
2c=290g-180g
2c=110g
c= 65g
