Does anyone know this.

What is the sum of these mixed numbers 2 1/8 + 4 3/8

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.

Which inequality statement describes the two numbers on a number line? "? 7 and a number 5 units to the right of ? 7"