Question

129.5×0.37-1.295×4+12.95×6.6用简算法怎么算？

Answer 1

129.5×0.37-1.295×4+12.95×6.6用简算法怎么算？

129.5×0.37-1.295×4+12.95×6.6
=129.5×0.37-129.5×0.04+129.5×0.66
=129.5×（0.37-0.04+0.66）
=129.5×0.99
=129.5×1-129.5×0.01
=129.5-1.295
=128.205

Answer 2

前面的129.5*0.37等于12.95*3.7 中间的1.295*4等于12.95*0.4 最后的12.95*6.6直接用，最后写成12.95*（3.7-0.4+6.6）就行了

Answer 3

扩大或缩小因数，通过结合律，将相关数字凑成整数，达到速算目的。
129.5×0.37-1.295×4+12.95×6.6
=1.295×37-1.295×4+1.295×66
=1.295×(37+66-4)
=1.295×99
=1.295×100-1.295×1
=129.5-1.295
=128.205

Answer 4

原式=1.295×100×0.37－1.295×4＋1.295×10×6.6
=1.295×37－1.295×4＋1.295×66
=1.295×（37－4＋66）
=1.295×99
=1.295×（100－1）
=1.295×100－1.295×1
=129.5－1.295
=128.205