You buy a total of pounds of two kinds of candy. One is for your upcoming party and costs $ 2.- per pound. However, you also treat yourself to a fancy kind that costs $ 10 per pound, to be enjoyed in solitude. You spend a total of $ 12.- and buy pounds of the gourmet candy.
Hint: Set up a system of two equations and solve it. Of course nobody said that you have to buy an integer number of pounds of candy.