递等式计算:(能巧算的要巧算) 2.8*0.9 5.4*10.1
问题描述:
递等式计算:(能巧算的要巧算) 2.8*0.9 5.4*10.1
答
=2.8×1—2.8×0.1 =5.4×10+5.4×0.1
=2.8-0.28 =54+0.54
=1.52 =54.54