125×（80-8）的简便运算

Answer 1

原式
=125x80-125x8
=10000-1000
=9000

或者
=125x72
=125x(8x9)
=(125x8)x9
=1000x9
=9000

供参考。

Answer 2

原式
=125x80-125x8
=10000-1000
=9000
或者
=125x72
=125x(8x9)
=(125x8)x9
=1000x9
=9000
供参考。

Answer 3

乘法分配律为：两个数的和与一个数相乘，先将它们与这个数分别相乘，再相加，积不变．即：（a+b）×c=a×c+b×c．反过来则：a×c+b×c=（a+b）×c
125× ( 80-8)
= 125×80-125×8
= 10,000-1000
= 9000

Answer 4

=125x80-125x8
=10000-1000
=9000
或者
=125x72
=125x(8x9)
=(125x8)x9
=1000x9
=9000