15. You are given a gold coin originally purchased by your great-great grandfather 50 years ago. He paid $1.00 for it at the time. Checking with Coins-R-Us you find the coin is now worth $450. If you sell it now, what will be the rate of return? Hint: now this obviously isn't an annuity problem, so you are down to two possible equations. This is another one where drawing a time line really helps you to visualize what's going on