Bunuel
In a common carnival game, a player tosses a penny from a distance onto the square surface of a table, which is 1 inch^2 in area. If the penny, which is 3/4 inch in diameter, falls entirely inside a square, the player wins; otherwise, he loses. If the penny lands on the table, what is the probability of winning?
A. 1/256
B. 1/32
C. 1/16
D. 1/8
E. 1/4
Are You Up For the Challenge: 700 Level Questions: 700 Level QuestionsThe square measures 1 inch by 1 inch. The radius of the penny is 3/8 of an inch. For the penny to land entirely within the square, the penny's center must be at least 3/8 of an inch from the left edge of the square, and at least 3/8 of an inch from the right edge of the square. Similarly it must land 3/8 of an inch from the top edge and 3/8 of an inch from the bottom edge. That only leaves a 1/4 by 1/4 inch square in the middle of the table on which the center of the penny can land.
From the answer choices, I'm guessing the question means to tell us that the center of the penny lands in a random spot somewhere on the table. If that's true, then the 'winning' area is 1/16 square inches, and the total area is 1 square inch, and the probability of winning is thus (1/16)/1 = 1/16.
But I'm just guessing that's what the question means from the answer choices. It would be perfectly reasonable reading the question to assume the penny 'lands' on the table if any part of the penny hits the table, even if it's just the edge of the penny hitting the edge of the table. Then as long as the center of the penny 'lands' no further than 3/8 of an inch from an edge of the table, it hits the table. Then there's a much larger square the penny can 'land' on -- it would measure 1 + 3/8 + 3/8 inches on each side, or 7/4 inches on each side, for a total area of 49/16 square inches. Then the probability of 'winning' is (1/16)/(49/16) = 1/49.