Răspuns :
23×32=736 23 x
=(20+3)x(30+2)= 32
=20x30+20x2+3x30+3x2= ------
=600+40+90+6= 46+
=600+130+6= 69
=736 -----------
736
17×71=
=(10+7)x(70+1)= 17 x
=10x70+10x1+7x70+7x1= 71
=700+10+490+7= --------
=700+500+7= 17 +
=1207 119
---------
1207
=(20+3)x(30+2)= 32
=20x30+20x2+3x30+3x2= ------
=600+40+90+6= 46+
=600+130+6= 69
=736 -----------
736
17×71=
=(10+7)x(70+1)= 17 x
=10x70+10x1+7x70+7x1= 71
=700+10+490+7= --------
=700+500+7= 17 +
=1207 119
---------
1207