Răspuns :
8*13=4*26=2*52=52+52=104
2*436=436+436=872
3*45=45+45+45=90+45=135
2*436=436+436=872
3*45=45+45+45=90+45=135
8 × 13 = 8 × ( 10 + 3 ) = 8 × 10 + 8 × 3 = 80 + 24 = 104
2 × 436 = 2 × ( 400 + 30 + 6 ) = 2 × 400 + 2 × 30 + 2 × 6 = 800 + 60 + 12 = 872
3 × 45 = 3 × ( 40 + 5 ) = 3 × 40 + 3 × 5 = 120 + 15 = 135
2 × 436 = 2 × ( 400 + 30 + 6 ) = 2 × 400 + 2 × 30 + 2 × 6 = 800 + 60 + 12 = 872
3 × 45 = 3 × ( 40 + 5 ) = 3 × 40 + 3 × 5 = 120 + 15 = 135