You have 3 coins and are told one of them is a heads. What is the probability that all 3 are heads?

There are stones in two dimension array, and given a known length rope, determine what’s the maximum number of stones you can use the rope to surround? (the rope must be enclosed)

I flip a coin three times, and tell you I got heads on one of the flips. What’s the probability I got 2 heads and one tails (not necessarily in that order).

If an nxn matrix is populated with 0 or 1 randomly, what is the probability that it is non-singular.

What is a fair payout for a game where you draw a number from 1-12 and win whatever number you draw, but you can either keep the first card you draw or replace it and draw a second card?

You have 50 white marbles and 50 black marbles, you are going to place these marbles into two buckets however you would like. Then you are going to randomly select a marble from one of the two buckets. How can you stack the odds so you pull out a black marble?

M,J,J,A,S,O, what is next in the series?

Game 1 pays $20 if you flip heads and you flip the coin 4 times, game 2 pays $500 if you flip heads all 4 times. Which game do you pick?

If three points are randomly selected on the sides of a square, what is the probability that the triangle formed by the points contains the center of the square.

What is the probability that three random points on a unit circle would form a triangle that includes the center of the unit circle?