Question

兩個因數(shù)相乘，一個因數(shù)擴大3倍，另一個因數(shù)擴大4倍，積________．

Answer 1

應擴大12倍
分析：兩個因數(shù)相乘，一個因數(shù)擴大3倍，另一個因數(shù)擴大4倍，根據(jù)積的變化規(guī)律可知，積應擴大3×4=12倍．
解答：兩個因數(shù)相乘，一個因數(shù)擴大3倍，另一個因數(shù)擴大4倍，
3×4=12．
則積應擴大12倍．
故答案為：擴大12倍．
點評：積的變化規(guī)律有：一個因數(shù)擴大n倍，另一個因數(shù)不變，則積也擴大n倍．一個因數(shù)擴大n倍，另一個因數(shù)擴大m倍，則積也擴大m×n倍，一個因數(shù)擴大n倍，另一個因數(shù)縮小n倍，則積不變等．