Question

1.55÷3.9的商精確到百分位是

 

．

Answer 1

分析：根據(jù)小數(shù)除法法則計(jì)算到小數(shù)點(diǎn)后第三位，再將商精確到百分位．

解答：解：1.55÷3.9≈0.40．

故答案為：0.40．

點(diǎn)評(píng)：考查了小數(shù)除法和近似數(shù)及其求法．小數(shù)除法法則：除數(shù)是小數(shù)的除法，先利用除法中除數(shù)與被除數(shù)同時(shí)擴(kuò)大或縮小相同的倍數(shù)商不變，去掉除數(shù)的小數(shù)點(diǎn)，然后再按整數(shù)除法計(jì)算，商的小數(shù)點(diǎn)與被除數(shù)的小數(shù)點(diǎn)對(duì)齊．精確到百分位要看小數(shù)點(diǎn)后第三位的數(shù)字進(jìn)行四舍五入．