According to recent statistics from the MTA, 80% of the
subway cars on the Q line were found to have clean seats
and floors.
Express this percent as a fraction and then as a fraction in
lowest terms.

At the beginning of year 1, carlos invests $600 at an annual compound interest rate of 4%. he makes no deposits to or withdrawals from the account. which explicit formula can be used to find the account's balance at the beginning of year 5? what is, the balance?