Question

简便计算125×1.2×1.5×1.8×3.2

Answer 1

125×1.2×1.5×1.8×3.2
=125*3.2*1.2*1.5
=125*（8*0.4）*（0.6*2）*1.5【去括号，乘法结合律】
=125*8*0.4*0.6*（2*1.5）
=1000*0.4*0.6*3【自己会了么？！】
=

Answer 2

上式
=125×（8×0.4）×（3×0.4）×（3×0.5）×（3×0.6）
=（125×8）×0.4×0.4×（0.5×0.6）×3^3
=1000×0.4×0.4×0.3×3^3
=4^2×3^4 （→也可以化成36^2，如果暗记平方值，会比较方便）
=1296

Answer 3

=125 x (6/5) x (3/2) x ( 9/5) x (16/5)
= (125 x 6 x 3 x 9 x 16 ) / (5 x2 x5 x 5)
=(125 x 2 x3 x3 x9 x16)/ (125 x2 )
=3x3x9x16=81x16=1296