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题库 / Prep2007E2-PS-143
Of the 50 employees of a certain company, 30 earn an average (arithmetic mean) salary of $30,000, 15 earn an average salary of $40,000, and 5 earn an average salary of $60,000. What is the average salary earned by the employees of this company?
$30,000
$36,000
$40,000
$45,000
$50,000
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