The lifetimes of computer hard drives produced by hishobi company are normally distributed with a mean of 75 months and a standard deviation of 8 months. What lifetime (in months) is exceeded by 10% of the hard drives

The lifetime is months is 85.24 monthsStep-by-step explanation:In this question you are supposed to find the months "X' that is exceeded by 10% of the hard drives.Exceeded by 10% means a value X on the frequency distribution table that is to the right of the mean score of 75 months showing 10% more.This means exceeding 10% will be months above 0.9 (from 100-90=90%=1-0.9=0.1 as a decimal)In the standard normal distribution table, look for 0.9, closest value is 0.8997 which gives z=1.2 for y-axis and for x-axis 0.08 to give 1.28So you have z=1.28, mean μ=75 and δ=8, finding X will givesYou apply the formula;P(z>X-75/8)P(z>1.28)=0.1z=X-μ /δ1.28=(X-75)/88*1.28=X-7510.24=X-7510.24+75=XX=85.24 monthsLearn MorePercentile in Normal distribution :: normally distributed, mean, standard deviation, exceeds#LearnwithBrainly