Question

72x56+28x56用简便方法？

65x32+67×65-65

Answer 1

72×56+28×56
=56×（72+28）
=56×100
=5600
65×32+67×65-65
=65×（32+67-1）
=65×98
=65×（100-2）
=6500-130
=6500-（200-70）
=6500-200+70
=6300+70
=6370

Answer 2

72×56+28×56
=56×(72+28)
=56×100
=5600
乘法分配律的逆用

Answer 3

72x56+28x56
=(72+28)x56
=100x56
=5600

Answer 4

=（72+28）×56
=100×56
=5600

Answer 5

72*56+28*56
=(72+28)*56
=100*56
=5600