Question

0.8×0.25×0.4×12.5等于几？ 简便运算 第等式

Answer 1

0.8×0.25×0.4×12.5
=12.5×0.8×0.4×0.25
=10×0.1
=1

Answer 2

0.8×0.25×0.4×12.5
=(0.8×12.5)×(0.25×0.4)
=10×0.1
=1
8×125=1000，0.8×12.5小数点前进两位，所以结果1000也得前进两个小数点就等于10， 0.4×12.5同等。
记住一些快计算，比如25×4=100，
125×8=1000，
25×6=150，
125×2=250，
25×8=200，
125×4=500等等

Answer 3

运用乘法结合律，改变乘数的位置结果不变，所以原式等于（0.8×12.5）×（0.25×0.4）=10×0.1=1

Answer 4

0.8×0.25×0.4×12.5

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=0.8×12.5×0.25×0.4

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=10×0.1

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=1

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答：先算0.8×0.25的积，再乘以0.25×0.4的积，就好算了。

Answer 5

=0.8*12.5*0.25*0.4
=10*0.1
=1