Given a mean of 62 and a standard deviation of 5, convert the random variables to Z-scores, then use a standard normal table below to find the probability.
Pr[62 ≤ X ≤ 67] =
P(62 < X < 67)
= P((62 - )/< (X - )/< (67 - )/)
= P((62 - 62)/5 < Z < (67 - 62)/5)
= P(0 < Z < 1)
= P(Z < 1) - P(Z < 0)
= 0.8413 - 0.5
= 0.3413
Given a mean of 62 and a standard deviation of 5, convert the random variables to...
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