某校課外環(huán)保小組對本市的十個地方抽樣做空氣的含塵調(diào)查.數(shù)據(jù)如下(單位:克/立方米):
0.01,0.04,0.03,0.04,0.02,0.03,0.04,0.03,0.01,0.03.
(1)說出這組數(shù)據(jù)的眾數(shù)和它的實際意義;
(2)如果國家環(huán)保局對大氣飄塵的要求為平均值不超過0.025克/立方米,問該市的空氣是否符合國家環(huán)保要求?
解:
(1)0.03克/立方米出現(xiàn)了四次,次數(shù)最多,眾數(shù)為0.03克/立方米;
其實際意義是反映了空氣質(zhì)量狀況的集中趨勢.
(2)因為0.03克/立方米>0.025克/立方米,所以該市的空氣不符合國家環(huán)保要求.
分析:(1)找出數(shù)據(jù)中出現(xiàn)次數(shù)最多的數(shù),即為眾數(shù).
(2)求出這組數(shù)的平均數(shù),與0.025克/立方米比較大小就可以.
點評:考查了眾數(shù)和平均數(shù)的概念和它們在實際中的應用.