Question

In: Statistics and Probability

Weights of men are normally distributed with a mean of 189 lb and a standard deviation...

Weights of men are normally distributed with a mean of 189 lb and a standard deviation of 39 lb. If 14 men are randomly selected, find the probability that they have weights with a mean greater than 174 lb.

Expert Solution

Solution :

Given that,

mean = = 189

standard deviation = = 39

n = 14

=189

₌ / $\sqrt$ n = 39 $\sqrt$ 14 = 10.4232

P ( > 174 )

= 1 - P ( < 174 )

= 1 - P ( - /) < ( 174 - 189 / 10.4232)

= 1 - P ( z <- 15 / 10.4232 )

= 1 - P ( z < -1.44)

Using z table

= 1 - 0.0749

=0.9251

Probability = 0.9251

orchestra answered 2 years ago

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