If there are 9 white balls and one black ball in a bag. The white balls are valued at 10 dollars and black ball at 100 dollars. How much are you willing to pay for each pull from the bag (only one ball per pull) but you can pull as many times as you wanted.
Before you start pulling balls you must choose how much you are willing to pay for each pull. After each pull you keep the ball (it doesn't go back in the bag).