Question

【題目】兩個(gè)因數(shù)的小數(shù)位數(shù)一共是3，積的小數(shù)位數(shù)也一定是3．　 　．

Answer 1

【答案】錯(cuò)誤

【解析】

試題分析：根據(jù)小數(shù)乘法的計(jì)算法則：先按照整數(shù)乘法法則算出積，再看因數(shù)中一共有幾位小數(shù)，就從積的右邊向左數(shù)出幾位，點(diǎn)上小數(shù)點(diǎn)．兩個(gè)因數(shù)的小數(shù)位數(shù)一共是3，所以積的小數(shù)位數(shù)也是3．但是小數(shù)的末尾去掉0，小數(shù)的大小不變，如果這兩個(gè)因數(shù)的乘積末尾有0，那么小數(shù)的位數(shù)就不是3，據(jù)此判斷．

解：計(jì)算出來的積應(yīng)該是三位小數(shù)，但是會(huì)出現(xiàn)積末尾有零的現(xiàn)象，當(dāng)點(diǎn)上小數(shù)點(diǎn)后，根據(jù)小數(shù)的基本性質(zhì)會(huì)把小數(shù)末尾的零去掉，所以兩個(gè)因數(shù)的小數(shù)位數(shù)一共是3，積的小數(shù)位數(shù)不一定是3．

故答案為：錯(cuò)誤．