An investment company sells 3 types of pooled funds, Standard (S), Deluxe (D), and Gold (G). Each unit of S contains 12 shares of stock A, 16 of Stock B, and 8 of Stock C. Each unit of D contains 20 shares of Stock A, 12 shares of stock B and 28 of Stock C. Each unit of G contains 32 shares of A, 28 of B and 36 of Stock C.

Suppose an investor wishes to purchase exactly 220 shares of Stock A, 176 shres of stock B and 264 sharss of Stock C by buying units of the 3 funds. Determine those combinations of units of S,D and G which will meet the investors requirements exactly.

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