Three unbiased coins are tossed, what is the probability of getting at least 2…

Step-by-Step Solution

To find the probability of getting at least 2 tails when tossing three unbiased coins, we first determine the total number of possible outcomes and then identify the favorable ones.

1. Identify the Sample Space:

   When tossing three coins, each coin has 2 possibilities (Head or Tail). The total number of outcomes is 2*2*2 = 8.

   The outcomes are: {HHH, HHT, HTH, THH, HTT, THT, TTH, TTT}.

2. Identify Favorable Outcomes:

   "At least 2 tails" means we are looking for outcomes that have either 2 tails or 3 tails.

   • Outcomes with exactly 2 tails: {HTT, THT, TTH}

   • Outcomes with exactly 3 tails: {TTT}

   • Total favorable outcomes = 3 + 1 = 4.

3. Calculate Probability:

   • Probability = Favorable outcomes / Total outcomes

   • Probability = 4 / 8 = 1/2.