In Europe tennis balls are sold in packages of four, but in North America they are sold in packages of three.
16. In Europe tennis balls are sold in packages of four, but in North America they are sold in packages of three. Let X1 be the number of European packages of tennis balls, and let X2 be the number of American or Canadian packages of tennis balls. Draw the indifference curve through the bundle (6,8) of someone who uses a lot o