MAT 171 Sections 3.1-3.3

A train ticket in a certain city is $2.00. People who use the train also have the option of purchasing a frequent rider pass for 18.75 each month. With the pass, each ticket costs only $1.25. Determine the number of times in a month the train must be used so that the total monthly cost without the pass is the same as the monthly cost with the pass.

You inherit $10,000 with the stipulation that for the first year the money must be invested in two stocks paying 6% and 11% annual interest, respectively. How much should be invested at each rate if the total interest earned for the year is to be $700?