4.9×0.06的積一定是四位小數(shù)位數(shù)．________．
錯誤
分析：根據(jù)小數(shù)乘法的計算法則：先按照整數(shù)乘法法則算出積，再看兩個因數(shù)中一共有幾位小數(shù)，就從積的右邊向左數(shù)出幾位，點上小數(shù)點．由此解答．
解答：根據(jù)小數(shù)乘法的計算法則可知：積的小數(shù)位數(shù)等于兩個因數(shù)小數(shù)位數(shù)的和，4.9是一位小數(shù)，0.06是兩位小數(shù)，所以積一定是三位小數(shù)．
故答案為：錯誤．
點評：此題考查的目的是掌握小數(shù)乘法的計算法則，明確：積的小數(shù)位數(shù)等于兩個因數(shù)小數(shù)位數(shù)的和．
