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The weights of members of a baseball league are normally distributed with a mean of 176 pounds and a standard deviation of 11.4 pounds consider a league membership of 120 members how many of the members will wait 165 pounds or more
A 67
B76
C 80
D 100

 Apr 2, 2019
 #1
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\(\text{Let }\Phi(x) \text{ be the CDF of the standard normal distribution}\\ P[\text{weight > 165}] = 1 - P[\text{weight < 165}] = \\ 1 - \Phi\left(\dfrac{165-176}{11.4}\right)\approx \\ 1 - \Phi(-0.964912) =p \text{ (meaning you figure out what }p \text{ is)}\)

 

\(p\cdot 120 = ?\\ \text{match what you get above with the choice list}\)

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 Apr 2, 2019

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