2nd question for IOE engineers?

Question

An investor has $ 30 to invest amongst 4 fixed income securities.
He can buy these securities in unit amounts (like 1 units of security
1, 1 unit of security 2 etc.). The table below gives the value of each
security at the end of year one. This investor wants to find how
much he is to invest in each security so to to maximize his wealth
at the end of the year.
_____________1 2 3 4
Cost of one unit 8 4 14 12
Year end value 10 7 16 10

please solve by using total enumeration. I would also appreciate it if you could show your work and explain it.
thanks iin advance!

Answer 1

I would put that question into the mathematics forum, not engineering....