已知樣本數(shù)據(jù)l,0,6,l,2,下列說法不正確的是( )
A.中位數(shù)是6
B.平均數(shù)是2
C.眾數(shù)是1
D.極差是6
【答案】分析:分別計算該組數(shù)據(jù)的中位數(shù)、眾數(shù)、平均數(shù)及極差差后找到正確的答案即可.
解答:解:在已知樣本數(shù)據(jù)l,0,6,l,2,中,平均數(shù)是2;
極差=6-0=6;
數(shù)據(jù)1出現(xiàn)兩次,最多,故眾數(shù)為1.
所以根據(jù)中位數(shù)的定義,中位數(shù)是1,所以A不正確.
故選A.
點評:本題考查平均數(shù)和中位數(shù).一組數(shù)據(jù)的中位數(shù)與這組數(shù)據(jù)的排序及數(shù)據(jù)個數(shù)有關(guān),因此求一組數(shù)據(jù)的中位數(shù)時,先將該組數(shù)據(jù)按從小到大(或按從大到。┑捻樞蚺帕校缓蟾鶕(jù)數(shù)據(jù)的個數(shù)確定中位數(shù):當(dāng)數(shù)據(jù)個數(shù)為奇數(shù)時,則中間的一個數(shù)即為這組數(shù)據(jù)的中位數(shù);當(dāng)數(shù)據(jù)個數(shù)為偶數(shù)時,則最中間的兩個數(shù)的算術(shù)平均數(shù)即為這組數(shù)據(jù)的中位數(shù).