The distribution of the numbers of hours that students at a certain college studied for final exams has a mean of 12 hou
The distribution of the numbers of hours that students at a certain college studied for final exams has a mean of 12 hours and a standard deviation of 3 hours.Which of the following numbers of hours are within 2 standard deviations of the mean of the distribution?Indicate all such numbers
A.2 B.5 C10 D.14 E.16
A.2 B.5 C10 D.14 E.16
英語(yǔ)人氣：634 ℃時(shí)間：2020-03-29 19:59:12
優(yōu)質(zhì)解答
答案選CDE麻煩給下解答思路唄大致意思是學(xué)生為學(xué)習(xí)，學(xué)習(xí)時(shí)間平均為12小時(shí)，一個(gè)標(biāo)準(zhǔn)區(qū)間是3小時(shí)。問(wèn)以下哪些時(shí)間處于平均時(shí)間加減2個(gè)標(biāo)準(zhǔn)區(qū)間內(nèi)這個(gè)就是高斯分布的概念題啦，就是看在12-2×3=6和12+2×3=18，看看哪些選項(xiàng)在6到18之間啦
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