ex nr.12 va rog dau coroana
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14x5= (10x5)+(4x5)= 50+20=70
16x4=(10x4)+(6x4)=40+24=64
19x9= (10x9)+(9x9)=90+81=171
13x6= (10x6)+(3x6)=60+18=78
34x8= (30x8)+(4x8)=240+32=272
5x68= (60x5)+(5x8)=300+40=340
72x3= (70x3)+(2x3)=210+6=216
28x2= (20x2)+(8x2)=40+16=56
9x75= (70x9)+(5x9)=630+45=675