datamanagement数学题researchershaveobservedthatregularsmokershaveanaveragelifespanthatisnormallydistributedandis68yearswithastandarddeviationof10years.whatpercentofsmokerswilllivebeyondage76?
<p>问题：datamanagement数学题researchershaveobservedthatregularsmokershaveanaveragelifespanthatisnormallydistributedandis68yearswithastandarddeviationof10years.whatpercentofsmokerswilllivebeyondage76?<p>答案：↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">邓华锋的回答：<div class="content-b">网友采纳 此题本意是有正态分布曲线N(68,10),要求计算P（X>=76) u=(X-μ)/σ=(76-68)/10=0.8,查标准正态分布表可得Φ(0.8)=0.7881 P（X>=76）=(1-Φ(u))/2=(1-0.7881)/2=0.106 即能够超过76岁的概率是10.6%
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