Answer: I must invest $85424.14 today in order to buy a Ferrari nine years from now on the day I turn 30.
We have
Price of the Ferrari nine years from now (Future Value - FV) $215000
Expected Rate of return on the mutual fund (r) 10.8%
Time until I turn 30 (n) 9 years
We can calculate the Present Value (PV) or the money to be invested today as
[tex]\mathbf{PV = \frac{FV}{(1+n)^{n}}}[/tex]
[tex]PV = \frac{215000}{(1+0.108)^{9}}[/tex]
[tex]\mathbf{PV = 85424.14022}[/tex]