E. Mark has $20 in his bank account. He saves $5 each week. How much money does Mark have in his account after 9 weeks? Use w to represent the number of weeks and t to represent the total amount Mark has after any number of weeks.
Monica knows that she should spend no more than 1/3 of her income on her rent. She really wants to move into a cool condo downtown and has found a great place where the rent is $2,300 per month. Based on that, how much should Monica earn each month to afford the rent on her cool new place?
