Greg bought a gold coin for $9,000. If the value of the coin increases at a constant rate of 12% every 5 years, how many years will it take for the coin to be worth $20,000?
Approximately 35 years (35.23).
If the price increases by 12% every five years, to get the value after five years we multiply by
So the value after
So we now want to find out when the value will be $20000. So
Take logs of both sides and use rules of logs on LHS to bring down the n:
The coin reaches $20000 value after roughly 35 years.