Coins
Let us have a look at some probability questions based on Coins.
Q. Three unbiased coins are tossed. What is the probability of getting:
A. All tails
B. Two tails
C. One tail
Explanation:
Sample space S = {HHH, THH, HTH, HHT, HTT, THT, TTH, TTT}, so a total of 8 possible outcomes.
A. Favourable elementary events = {TT}, i.e. 1 favourable event. So, required probability = 1/8
B. Favourable elementary events = {HTT, THT, TTH}, i.e. 3 favourable events. So, required probability = 3/8
C. Favourable elementary events = {THH, HTH, HHT}, i.e. 3 favourable events. So, required probability = 3/8
Note: As the coin is unbiased, the probability of getting one tail will be the same as the probability of getting one head.