Question

給得數(shù)點(diǎn)上小數(shù)點(diǎn)．
4.2×3.8=1596　　
7.45×1.3=9685　　
2.15×4.2=9030
2.06×13=2678　　
5.3×4.2=2226　　
0.37×0.15=555．

Answer 1

解：4.2×3.8=15.96，
7.45×1.3=9.685，
2.15×4.2=9.030，
2.06×13=26.78，
5.3×4.2=22.26，
0.37×0.15=0.0555．
分析：積的小數(shù)位數(shù)等于兩個(gè)因數(shù)的小數(shù)位數(shù)和，據(jù)此解答．
點(diǎn)評(píng)：筆算兩個(gè)小數(shù)相乘，所得的積的小數(shù)位數(shù)，等于兩個(gè)因數(shù)中小數(shù)的位數(shù)之和．