Question

If we perform the experiment "Toss Three Coins", what is the probability of getting 3 tails?
A. 1/8
B. 3/8
C. 1/2

Answer 1

If you toss 3 coins, you have 8 possible results, then it's A.

Answer 2

1/2 chance first coin will be tails
1/2 chance second coin will be tails
1/2 chance third coin will be tails

If one of them is tails, we must multiply it by the probability of the second to get the probability of both things happening. Extending this to the third coin,

1/2 * 1/2 * 1/2 = 1/8