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posted by maria .
what is the probability by Pr( X ≥ 8) years where X is normally distributed with mean 5.24 and sd = 1.90?
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We estimate the probability by Pr( X ≥ 8) years where X is normally distributed with mean 5.24 and sd = 1.90.
Assuming normal distribution we want prob that x >=8
P(x>=8) = P(Z >= (8  5.24)/1.90) = P(Z >= 1.45) = 1  P(Z<1.45) = 
use a zscore table to find the portion of the population below 1.45 sd above the mean
looks like about .93
so prob X ≥ 8 is ... 1  .93
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