What is the answer to this problem 3=4n-2

How do you answer this question? (step by step)

According to the data set, where should the upper quartile line of the box plot be placed?

Tim's phone service charges $26.39 plus an additional $0.21 for each text message sent per month. if tim's phone bill was $31.64, which equation could be used to find how many text messages, x, tim sent last month?