脱式计算,能用简便算法的要用简便算法.5.4×910+3.6÷109+0.978×3796-314+3459×[34-(716-14)][47-(18.875-1÷815)]÷0.46×4625.-数学
题文
脱式计算,能用简便算法的要用简便算法. 5.4×
78×
6-3
[47-(18.875-1÷
|
答案
①5.4×
=5.4×0.9+3.6×0.9+0.9×1 =0.9×(5.4+3.6+1) =0.9×10 =9; ②78×
=(79-1)×
=79×
=3-
=2
③6-3
=3+3+ |