| 看谁算得快. 0.36+1.7= | × = | 0.32×0.05= | 1.2÷ = |
× ÷ × = | 6.8-1.08= | 50×30%= | - - = |
| 0.18÷0.12= | ( + )×8= |
| 0.36+1.7=2.06, | × = , | 0.32×0.05=0.016, | 1.2÷ =1.4, |
× ÷ × = , | 6.8-1.08=5.72, | 50×30%=15, | - - = , |
| 0.18÷0.12=1.5, | ( + )×8=9. |
,0.016,1.4,
,5.72,15,
,1.5,9.分析:
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先把除法变成乘法,再运用乘法分配律简算;
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根据连续减去两个数等于减去这两个数的和来简算;(
+
)×8运用乘法分配律简算;其它题目根据运算法则直接求解.点评:
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是常见的一类口算题,不要算成了1,要按照计算的顺序或运算定律求解.
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