考點:小數(shù)乘法
專題:運算順序及法則
分析:根據(jù)兩個因數(shù)的小數(shù)位數(shù)直接判斷即可.
解答:
解:(1)1.425×0.03,1.425是3位小數(shù),0.03是2位小數(shù),
它的積的末尾的數(shù)是5,不是0,所以積的小數(shù)的位數(shù)就是:3+2=5位小數(shù);
(2)4.25×0.005,4.25是2位小數(shù),0.005是3位小數(shù),
它的積的末尾的數(shù)是5,不是0,所以積的小數(shù)的位數(shù)就是:2+3=5位小數(shù);
(3)3.458×0.29,3.458是3位小數(shù),0.29是2位小數(shù),
它的積的末尾的數(shù)是2,不是0,所以積的小數(shù)的位數(shù)就是:3+2=5位小數(shù);
(4)0.048×0.213,0.048是3位小數(shù),0.213是3位小數(shù),
它的積的末尾的數(shù)是4,不是0,所以積的小數(shù)的位數(shù)就是:3+3=6位小數(shù);
(5)4.48×3.4,4.48是2位小數(shù),3.4是1位小數(shù);
它的積的末尾的數(shù)是2,不是0,所以積的小數(shù)的位數(shù)就是:2+1=3位小數(shù);
(6)0.349×4.4,0.349是3位小數(shù),4.4是1位小數(shù);
它的積的末尾的數(shù)是4,不是0,所以積的小數(shù)的位數(shù)就是:3+1=4位小數(shù).
故答案為:5位小數(shù),5位小數(shù),5位小數(shù),6位小數(shù),3位小數(shù),4位小數(shù).
點評:這種類型的題目不需要計算出結(jié)果,根據(jù)兩個因數(shù)小數(shù)的位數(shù)直接判斷即可,如果積的末尾沒有0,那么積的小數(shù)位數(shù)就是兩個因數(shù)小數(shù)位數(shù)的和.