用简便方法计算 1.5.1÷4+4.9×25% 2.2又5/1×0.75+2.2×4/1 要交的.快.

问题描述:

用简便方法计算 1.5.1÷4+4.9×25% 2.2又5/1×0.75+2.2×4/1 要交的.快.

1.5.1÷4+4.9×25%
=5.1×0.25+4.9×0.25
=0.25(5.1+4.9)
=0.25×10
=2.5
2.2又5/1×0.75+2.2×4/1
=2.2×0.75+2.2×0.25
=2.2×(0.75+0.25)
=2.2