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Little’s law firm has just one lawyer. customers arrive randomly at an average rate of 6 per 8 hour workday. service times have a mean of 50 minutes and a standard deviation of 20 minutes. how long does a customer spend at little’s law firm on average?

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)

Ineed in figuring out this problem.