Question: U.S. Department of Labor

In 2001, the U.S. Department of Labor reported the average hourly earnings for U.S. production workers to be $14.32 per hour (The World Almanac 2003). A sample of 75 production workers during 2003 showed a sample mean of $14.68 per hour.

Assuming a population standard deviation σ = $1.45, determine if it can be concluded that an increase occurred in the mean hourly earnings since 2001. Use α = .05.