问题
解答题
用简便方法计算
①25×1.25×32
②(3.75-2.9+2.25)÷31%
答案
①25×1.25×32,
=25×1.25×4×8,
=(25×4)×(1.25×8),
=100×10,
=1000;
②(3.75-2.9+2.25)÷31%,
=(3.75+2.25-2.9)÷31%,
=(6-2.9)÷0.31,
=3.1÷0.31,
=10.
用简便方法计算
①25×1.25×32
②(3.75-2.9+2.25)÷31%
①25×1.25×32,
=25×1.25×4×8,
=(25×4)×(1.25×8),
=100×10,
=1000;
②(3.75-2.9+2.25)÷31%,
=(3.75+2.25-2.9)÷31%,
=(6-2.9)÷0.31,
=3.1÷0.31,
=10.