# Question

According to Collegeboard.com [http://www.college- board.com/] the national average salary for a plumber as of 2007 is $47,350. If we assume that the annual salaries for plumbers are normally distributed with a standard deviation of $5250, find the following:

a. What percentage earn below $30,000?

b. What percentage earn above $63,000?

a. What percentage earn below $30,000?

b. What percentage earn above $63,000?

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