Math 110 Course Resources - Implicit Differentiaion & Related Rates Course Packet on related rates The wholesale price p of e-tablet writing styluses in dollars is related to the supply x in thousands of units by 500p2 - x2 = 7984, If 4,000 styluses are available at the beginning of a week, and the price is rising at 24 cents per week, then supply is O falling O rising X at a rate of 120 X styluses per week