Răspuns:
14x5=(10x5)+(4x5)=50+20=70
13x6=(10x6)+(3x6)=60+18=78
72x3=(70x3)+(2x3)=210+6=216
16x4=(10x4)+(6x4)=40+24=64
34x8=(30x8)+(4x8)=240+32=272
28x2=(20x2)+(8x2)=40+16=56
19x9=(10x9)+(9x9)=90+81=171
5x68=(5x60)+(5x8)=300+40=340
9x75=(9x70)+(9X5)=630+45=675