You have 12 balloons to blow up for a party. You blow up 13 of them, and your friend blows up 5 of them. What fraction of the balloons still need blowing up?

Suppose that the price p (in dollars) and the weekly sales x (in thousands of units) of a certain commodity satisfy the demand equation 4p cubedplusx squaredequals38 comma 400. determine the rate at which sales are changing at a time when xequals80, pequals20, and the price is falling at the rate of $.20 per week.