÷ = | × = | 25×40%= | 7-0.82= |
+ = | ×5×18= | 4.05-2.8-0.7= | 5÷1%= |
÷ = , | × = , | 25×40%=10, | 7-0.82=6.18, |
+ = , | ×5×18=40, | 4.05-2.8-0.7=0.55, | 5÷1%=500. |
,
,10,6.18,
,40,0.55,500.分析:分数乘法:分子相乘的积做分子,分母相乘的积做分母;
分数除法:除以一个数(0除外)等于乘这个数的倒数;
×5×18运用乘法交换律简算;4.05-2.8-0.7根据减法的性质简算.
点评:本题考查了基本的运算,计算时要细心,注意把结果化成最简分数.
÷
=
×
=
+
=