Future value of a portfolio.

Rachel and Richard want to know when their current portfolio will be sufficient for them to retire. They have the following balances in their portfolio:

Money market account (MM): $33,000

Government bond mutual fund (GB):$130,000

Large capital mutual fund (LC):$106,000

Small capital mutual fund (SC):$71,000

Real estate trust fund (RE):$88,000

Rachel and Richard believe they need at least $2400 to retire. The money market account grows at 3.0 % annually, the government bond mutual fund grows at 5.5% annually, the large capital mutual fund grows at 8.5 %, annually, the small capital mutual fund grows at 13.5 % annually, and the real estate trust fund grows at 3.0 % annually. With the assumption that no more funds will be deposited into any of these accounts, how long will it be until they reach the $2,400.00 goal?

Rachel and Richard will need to invest their accounts for ???????????? or more years to reach $2400,00.