Roulette Wheel: The game of roulette involves spinning a wheel with 38 slots

Question

Roulette Wheel:  The game of roulette involves spinning a wheel with 38 slots: 18 red, 18 black, and 2 green. A ball is spun onto the wheel and will eventually land in a slot, where each slot has an equal chance of capturing the ball.

a) You watch a roulette wheel spin 7 consecutive times and the ball lands on a red slot each time. What is the probability that the ball will land on a red slot on the next spin?

(please round to four decimal places)

b) You watch a roulette wheel spin 320 consecutive times and the ball lands on a red slot each time. What is the probability that the ball will land on a red slot on the next spin? (please round to four decimal places)

Answer 1

a) 2/38 = 1/19 = about 0.0526

38 possible outcomes, only 2 are red, odds are 2/38= 0.0526

b) 2/38 = 0.0526

same with flipping a coin. It can turn up heads for a million times, the next flip is still just P(H)=1/2 = .5

the coin has no memory. the roulette wheel has no memory either