Question

甲、乙兩支女子曲棍球隊(duì)在去年的國(guó)際聯(lián)賽中,甲隊(duì)平均每場(chǎng)進(jìn)球數(shù)為3.2,全年比賽進(jìn)球個(gè)數(shù)的標(biāo)準(zhǔn)差為3；乙隊(duì)平均每場(chǎng)進(jìn)球數(shù)為1.8,全年比賽進(jìn)球個(gè)數(shù)的標(biāo)準(zhǔn)差為0.3.下列說(shuō)法正確的個(gè)數(shù)為(    )

①甲隊(duì)的技術(shù)比乙隊(duì)好  ②乙隊(duì)發(fā)揮比甲隊(duì)穩(wěn)定  ③乙隊(duì)幾乎每場(chǎng)都進(jìn)球  ④甲隊(duì)的表現(xiàn)時(shí)好時(shí)壞

A.1個(gè)           B.2個(gè)            C.3個(gè)             D.4個(gè)

Answer 1

解析：四種說(shuō)法都正確.甲隊(duì)的平均進(jìn)球數(shù)多于乙隊(duì)；乙隊(duì)標(biāo)準(zhǔn)差較小,說(shuō)明技術(shù)水平穩(wěn)定；甲隊(duì)平均進(jìn)球數(shù)是3.2,但其標(biāo)準(zhǔn)差卻是3,離散程度較大,由此可判斷甲隊(duì)表現(xiàn)不穩(wěn)定；乙隊(duì)平均進(jìn)球數(shù)是1.8,標(biāo)準(zhǔn)差只有0.3,每場(chǎng)進(jìn)球數(shù)相差不多,可見(jiàn)乙隊(duì)的確很少不進(jìn)球.

答案：D