There are white spaces and black spaces on the board, as shown. You have a ruler three spaces long that are you going to put on the board... a random space is picked out of the 49 spaces (either random 7 to determine the row, and then random 7 to determine the column, or just random 49 to determine the square number, whatever, somehow you randomly determine, with equal chances, a square from the board). This random square on the board is where you start the ruler, and you place it facing any of the four orthogonal directions (left, right, up, down), randomly (ie, random out of 4). Obviously if it's in the corner it's only random out of 2 directions, or 3 directions if it's a side piece. (Remember, the ruler is 3 spaces long)
1. What is the probability that the ruler's end will fall on a white space?
2. What is the probability that the ruler's end will fall on a black space?
3. What is the probability that the ruler's end will land on a color that is the same color as the space under the ruler's beginning? (ie, one end is on black, the other end is on black, or one is on white and the other end is on white)
Question
unreality
You have a 7x7 board that looks like this:
There are white spaces and black spaces on the board, as shown. You have a ruler three spaces long that are you going to put on the board... a random space is picked out of the 49 spaces (either random 7 to determine the row, and then random 7 to determine the column, or just random 49 to determine the square number, whatever, somehow you randomly determine, with equal chances, a square from the board). This random square on the board is where you start the ruler, and you place it facing any of the four orthogonal directions (left, right, up, down), randomly (ie, random out of 4). Obviously if it's in the corner it's only random out of 2 directions, or 3 directions if it's a side piece. (Remember, the ruler is 3 spaces long)
1. What is the probability that the ruler's end will fall on a white space?
2. What is the probability that the ruler's end will fall on a black space?
3. What is the probability that the ruler's end will land on a color that is the same color as the space under the ruler's beginning? (ie, one end is on black, the other end is on black, or one is on white and the other end is on white)
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