Răspuns :
2c+5p=9
1c+5p=7 /×2
2c+5p=9
2c+10p=14
_________faci scadere
../.. 5p=5
p= 5:5
p=1 un pix costa 1 leu
2c+5p=9
2c+1×5=9
2c+5=9
2c=9-5
2c=4
c=4:2
C=2 1caiet costa 2 lei
1c+5p=7 /×2
2c+5p=9
2c+10p=14
_________faci scadere
../.. 5p=5
p= 5:5
p=1 un pix costa 1 leu
2c+5p=9
2c+1×5=9
2c+5=9
2c=9-5
2c=4
c=4:2
C=2 1caiet costa 2 lei