Question

21.8×21.6-21.8×21.5+21.7×21.5-21.7×21.6用简便方法计算？

Answer 1

21.8×21.6-21.8×21.5+21.7×21.5-21.7×21.6
=21.8×(21.6-21.5)+21.7×(21.5-21.6)
=21.8×0.1-21.7×0.1
=(21.8-21.7)×0.1
=0.01

Answer 2

此题采用提取公因数方法进行简算，原式=21.8*（21.6-21.5）+21.7*（21.5-21.6）=21.8*0.1-21.7*0.1=0.1*（21.8-21.7）=0.1*0.1=0.01