How to change 54% to a decimal number

Which of the following is most likely the next step in the series? a3z, b6y, c9x, d12w, е15v, f18u

Write the rational number in lowest terms 99/-15

Part a: sam rented a boat at $225 for 2 days. if he rents the same boat for 5 days, he has to pay a total rent of $480. write an equation in the standard form to represent the total rent (y) that sam has to pay for renting the boat for x days. (4 points)