用豎式計算小數(shù)乘法,兩個因數(shù)的小數(shù)點必須對齊.
錯誤
分析:計算小數(shù)乘法,先按照整數(shù)乘法的法則算出積,再看乘數(shù)中一共有幾位小數(shù),就從積的右邊起數(shù)出幾位,點上小數(shù)點,不需要把兩個因數(shù)的小數(shù)點對齊,只要把這兩個小數(shù)的末尾數(shù)對齊,然后再進一步解答.
解答:計算小數(shù)乘法,不需要把兩個因數(shù)的小數(shù)點對齊,只要把這兩個小數(shù)的末尾數(shù)對齊;
所以,用豎式計算小數(shù)乘法,兩個因數(shù)的小數(shù)點必須對齊是錯誤的.
故答案為:×.
點評:小數(shù)乘法,按照整數(shù)乘法算出積,再看因數(shù)中一共有幾位小數(shù),就從積的右邊起,向左數(shù)出幾位,點上小數(shù)點,因此,只要把這兩個小數(shù)的末尾數(shù)對齊.