| 4.3÷4.3= | × ×7= | 1- - = | 1.5× = |
| 3.45-1.8= | 4.4× = | 7.2+0.8= | 2.8×0.25= |
| 解:4.3÷4.3=1, | × ×7=2, | 1- - =0, | 1.5× =1, |
| 3.45-1.8=1.65, | 4.4× =1.1, | 7.2+0.8=8, | 2.8×0.25=0.7. |
分析:计算
×
×7时,先把分子和分母交叉约分,然后再计算;把1-
-
改写成1-(
+
),从而简算;把2.8×0.25改写成0.7×(4×0.25),从而简算;
其它算式按照分数、小数四则运算的方法进行计算得解.
点评:此题考查基本的口算,注意运算符号和数据,能简算的要简算.
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