Question

In: Statistics and Probability

The average MCAT score follows a Normal distribution, with a mean of μ = 508 and...

The average MCAT score follows a Normal distribution, with a mean of μ = 508 and a standard deviation of σ = 8. What is the probability that the mean IQ score of 100 randomly selected people will be more than 510?

Solutions

Expert Solution

Solution :

Given that ,

mean = = 508

standard deviation = = 8

n = 100

=   = 508

= / n = 8 / 100 = 0.8

P( > 510) = 1 - P( < 510)

= 1 - P[( - ) / < (510 - 508) / 0.8 ]

= 1 - P(z < 2.50)

Using z table,    

= 1 - 0.9938

= 0.0062


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