You just turned 21 and were given a bank statement in your name showing a balance of $18,000. If your grandmother made equal deposits each year on your birthday, how much did she deposit if interest rates are 6%?

If she deposited $3,000 when you were born, and $3,000 when you were 6, how much did she make as a final deposit when you were 12 to end up with $18,000?