分析:(1)把被除數(shù)和除數(shù)分別擴大10倍,再計算;
(2)(3)把被除數(shù)和除數(shù)分別擴大100倍,再計算;
(3)先算94×65,然后從結(jié)果中從后向前數(shù)出四位,點上小數(shù)點即可;
(4)先算206×120,然后從結(jié)果中從后向前數(shù)出兩位,點上小數(shù)點即可;
(5)先算302×48,然后從結(jié)果中從后向前數(shù)出三位,點上小數(shù)點即可.
解答:解:8.49÷4.9≈1.73
7.21÷0.89≈8.10
0.94×0.65=0.611
2.06×120=247.2
3.02×4.8=14.496
35.96÷0.58=62
點評:遇到小數(shù)乘法,先把小數(shù)當整數(shù)乘,乘完之后所有因數(shù)的小數(shù)點加起來共有幾位,積上面就點幾位小數(shù)點.注意如果碰到因數(shù)有零的算式,要先加上零,再點小數(shù)點.遇到小數(shù)除法,如果除數(shù)是小數(shù),先把它擴大成整數(shù),被除數(shù)也擴大相應(yīng)的倍數(shù),其他就按整數(shù)除法做.