Question
In: Statistics and Probability
In a large population of college-educated adults, the mean IQ is 112 with standard deviation 25....
In a large population of college-educated adults, the mean IQ is 112 with standard deviation 25. Suppose 100 adults from this population are randomly selected for a market research campaign.
What is the probability that the sample mean IQ is lower than 105?
Solutions
Expert Solution
Solution :
Given that,
mean = 
= 112
standard deviation = 
= 25
n = 100
= 112
= /
n = 25/
100=2.5
P(
< 105) = P[(
-
) /
< (105-112) / 2.5]
= P(z <-2.8 )
Using z table
= 0.0026
probability= 0.0026
orchestra answered 3 years agoRelated Solutions
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