To solve this, write an equation.
300 is your starting balance, add this to your equation.
300
You get 7% more each year, but you can't multiply by 7% because that will make it decrease by 93%. You have at add 1 to 7%.
300(1.07)
Lastly, the 18 variable for the years.
300(1.07)^18
Solve the equation and get $1013.97968 or $1013.98