Q. If a fair coin is tossed 4 times, what is the probability, to the nearest thousandth, of getting exactly 2 tails?Answer:
Understand the problem: Understand the problem.We need to calculate the probability of getting exactly 2 tails in 4 tosses of a fair coin.
Determine total outcomes: Determine the total number of outcomes for 4 coin tosses.Since each coin toss has 2 possible outcomes (heads or tails), for 4 tosses, the total number of outcomes is 24.Total outcomes = 2×2×2×2=16
Determine favorable outcomes: Determine the number of favorable outcomes for getting exactly 2 tails.We can use the binomial coefficient for this, which is given by "n choose k" where n is the total number of events (4 coin tosses) and k is the number of successful events (2 tails).The binomial coefficient formula is C(n,k)=k!∗(n−k)!n!.C(4,2)=2!∗(4−2)!4!=(2∗1∗2∗1)(4∗3∗2∗1)=6
Calculate probability: Calculate the probability of getting exactly 2 tails.The probability is the number of favorable outcomes divided by the total number of outcomes.Probability = Favorable outcomes / Total outcomes = 166
Simplify and round: Simplify the probability and round to the nearest thousandth.Probability = 166=0.375When rounded to the nearest thousandth, the probability is 0.375.