What a coin, when spun into the air and allowed to land on the ground, or in one's hand will have facing upwards 50% of the time. However one must remember that each consecutive flip of the coin does not reduce the chance of it landing on heads, no matter how many previous heads have been flipped. However if you are a character in a play by Tom Stoppard you can be assured of your coin coming up heads every single time it is flipped.