Here we use the following notation:

• SI — sources of income.

     General properties of this type tasks:

• physical nature of SI — any possible;
• diversity of SI profitability — fixed;
• payback factor — absent;
• the need for statistical modeling — not is.

     Statement of the task:

• number of investment options, for each of them are given:
  • investment amount, which consists of two parts:
    • investor's own funds;
    • credit funds, involved by him;
• interest rate on the loan;
• number of SI types, for each of them are given:
  • SI sample description;
  • minimum and permissible numbers of being acquired SI samples;
  • cost of one SI;
  • expected specific income (per time unit) from exploiting one SI.

     Maximized quality criterion: relative income (per time unit) from SI exploitation.