Question

0.123×0.4的積有四位小數(shù)．

Answer 1

正確
分析：根據(jù)小數(shù)乘法的計(jì)算法則，先按照整數(shù)乘法的計(jì)算法則算出積，再看兩個(gè)因數(shù)一共有幾位小數(shù)，就從積的右邊起數(shù)出幾位點(diǎn)上小數(shù)點(diǎn)．據(jù)此解答．
解答：根據(jù)小數(shù)乘法的計(jì)算法則可知，積的小數(shù)位數(shù)等于兩個(gè)因數(shù)小數(shù)位數(shù)的和，0.123是三位小數(shù)，0.4是一位小數(shù)，所以積有四位小數(shù)．
因此，0.123×0.4的積有四位小數(shù)．
故答案為：正確．
點(diǎn)評(píng)：此題考查的目的是掌握判斷積有幾位小數(shù)的方法，明確：積的小數(shù)位數(shù)等于兩個(gè)因數(shù)小數(shù)位數(shù)的和．