=+19. Basketballs. A company that makes basketballs has the motto: “Our basketballs are ready to play.” Therefore, it is important to the company that the basketballs are inflated with the proper amount of air when shipped. Most basketballs are inflated to 7 to 9 pounds per square inch.

From a set of calibration data, the following statistics were measured:

X = 8.05 R = 0.65