John Roberts has $42,180.53 in a brokerage account, and he plans to contribute an additional $5,000 to the account at the end of every year. The brokerage account has an expected annual return of 12 percent. If John’s goal is to accumulate $250,000 in the account, how many years will it take for John to reach his goal?

John Roberts has $42,180.53 in a brokerage account, and he plans to contribute an additional $5,000 to the account at the end of every year. The brokerage account has an expected annual return of 12 percent. If John’s goal is to accumulate $250,000 in the account, how many years will it take for John to reach his goal?
I calculate that it will take him 11 years not considering inflation or taxes. I used my Quicken financial calculator to come up with this number.