第一道32*19+34*38
= 32 x 19 + 68 x 19
=( 32+ 68) x 19
= 100 x 19
= 1900
第二道12344*6789-12345*6788
= 12344*6788 + 12344 -12345*6788
= 12344*6788 -12345*6788 + 12344
= ( 12344 - 12345) x 6788 + 12344
= 12344 - 6788
= 5 556
第一道32*19+34*38
= 32 x 19 + 68 x 19
=( 32+ 68) x 19
= 100 x 19
= 1900
第二道12344*6789-12345*6788
= 12344*6788 + 12344 -12345*6788
= 12344*6788 -12345*6788 + 12344
= ( 12344 - 12345) x 6788 + 12344
= 12344 - 6788
= 5 556