According to the Bureau of Labor Statistics, the average weekly pay for a U.S. production worker was $441.84. Assume that available data indicate that production worker wages were normally distributed with a standard deviation of $90.

What is the probability that a worker earned between $400 and $500? (Round to four decimal places)

How much did a production worker have to earn to be in the top 20% of wage earners? (Round to two decimal places)

For a randomly selected production worker, what is the probability the worker earned less than $250 per week? (Round to four decimal places)