Question

34×0.25+0.25×5.56+0.25×(7.2+54)÷9用简便方法计算

用简便方法计算．
45.45÷9÷5
1.25+4.6+0.75
0.8×0.25×0.4×12.5
7.2×3.4+2.8×3.4．

Answer 1

（1）45.45÷9÷5
=5.05÷5
=1.01

（2）1.25+4.6+0.75
=1.25+0.75+4.6
=2+4.6
=6.6

（3）0.8×0.25×0.4×12.5
=（0.8×12.5）×（0.25×0.4）
=10×0.1
=1

（4）7.2×3.4+2.8×3.4
=（7.2+2.8）×3.4
=10×3.4
=34