central limit theorem

ssmmss

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May 23, 2014
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27% of all Americans earn 100K+. In a city of 2000 people, What is the probability that there will be between 500 and 600 earning 100K+.

My solution:

a = (500-2000(.27))/(square root of 2000(.27)(.73)) = -40/square root of 394.2 = -2.01466

b = (600-2000(.27))/(square root of 2000(.27)(.73)) = 60/square root of 394.2 = 3.022

Then I plug in the values into this site: http://davidmlane.com/hyperstat/z_table.html

and get 0.9768

Is this correct? Thank you.
 
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