Cash Flow Creation

Hi, I am having troubles figuring out the answer to this question:
You wish to save for an overseas trip and will start depositing $250 at the end each month until you have exceeded your target of $2,000. Assuming you can earn an interest rate of 12% p.a. (compounding monthly) on your deposited money, what is the accumulated amount you have to spend if you leave 2 months after the last deposit?
Could you please show your working. Thanks heaps! :), more