Here is a puzzle for you. At first glance, it would appear that there is not nearly enough information to answer this question. But when you graph the indifference curve and think about it a little, you will see that there is a neat, easily calculated solution. Kinko spends all his money on whips and leather jackets. Kinko's utility function is U(x, y) = min{4x, 2x + y}, where x is his consumption of whips and y is his consumption of leather jackets. Kinko is consuming 15 whips and 10 leather jackets. The price of whips is $10. You are to find Kinko's income.
(a) Graph the indifference curve for Kinko that passes through the point (15, 10). What is the slope of this indifference curve at (15, 10)? ____
(b) What must be the price of leather jackets if Kinko chooses this point? ____. Now, what is Kinko's income? _________