Ron is planning for the back-to-school rush at his store. Last year he estimated that he would need 168 notebooks, but he sold 200 notebooks. Explain how Ron can find the percent error of his estimate.

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?

What is the binomial expansion of (2x-3)^5

Iq scores for adults age 20 to 34 years are normally distributed according to n(120, 20). in what range does the middle 68% of people in this group score on the test?