Your friend tells you that if you let her keep 202020 of your Pokemon cards for three months, she will give you 222 cards extra when she returns your cards to you. What is the annual rate of interest she is willing to pay for the borrowed cards?
Note: Even though she only keeps your cards for three months, we can still calculate an annual interest rate.

Twelve different video games showing substance use were observed and the duration times of game play (in seconds) are listed below. the design of the study justifies the assumption that the sample can be treated as a simple random sample. use the data to construct a 99% confidence interval estimate of μ, the mean duration of game play. 4028 4316 4816 4650 4036 5010 4833 4331 4307