If the probability that the Islanders will beat the Rangers in a game is 0.71 , what is the probability that the Islanders will win at most two out of seven games in a series against the Rangers? Round your answer to the nearest thousandth.Answer:
Q. If the probability that the Islanders will beat the Rangers in a game is 0.71 , what is the probability that the Islanders will win at most two out of seven games in a series against the Rangers? Round your answer to the nearest thousandth.Answer:
Identify Formula and Values: Identify the binomial probability formula and the values of n, k, and p. The binomial probability formula is P(X=k)=C(n,k)⋅(p)k⋅(1−p)(n−k), where n is the number of trials, k is the number of successes, and p is the probability of success on a single trial. For this problem, n=7 (seven games in a series), p=0.71 (probability that the Islanders will beat the Rangers in a game), and k will take on the values k0, k1, and k2 because we are looking for the probability of the Islanders winning at most two games.
Calculate Probability for k=0: Calculate the probability for k=0. Using the binomial probability formula, we calculate P(X=0): P(X=0)=C(7,0)×(0.71)0×(1−0.71)7−0C(7,0) is the number of ways to choose 0 games out of 7, which is 1. (0.71)0 is 1 because any number to the power of 0 is 1. k=02 is k=03. Now we calculate k=03.
Calculate (0.29)7: Calculate (0.29)7. (0.29)7=0.29×0.29×0.29×0.29×0.29×0.29×0.29 This calculation gives us approximately 0.0005741. Now we can calculate P(X=0): P(X=0)=1×1×0.0005741=0.0005741.
Calculate Probability for k=1: Calculate the probability for k=1. Using the binomial probability formula, we calculate P(X=1): P(X=1)=C(7,1)⋅(0.71)1⋅(1−0.71)(7−1)C(7,1) is the number of ways to choose 1 game out of 7, which is 7. (0.71)1 is 0.71. (1−0.71)(7−1) is (0.29)6. Now we calculate (0.29)6.
Calculate (0.29)6: Calculate (0.29)6. (0.29)6=0.29×0.29×0.29×0.29×0.29×0.29 This calculation gives us approximately 0.001979. Now we can calculate P(X=1): P(X=1)=7×0.71×0.001979=0.00994049.
Calculate Probability for k=2: Calculate the probability for k=2. Using the binomial probability formula, we calculate P(X=2): P(X=2)=C(7,2)⋅(0.71)2⋅(1−0.71)(7−2)C(7,2) is the number of ways to choose 2 games out of 7, which is 2!⋅(7−2)!7!=21. (0.71)2 is approximately 0.5041. (1−0.71)(7−2) is (0.29)5. Now we calculate (0.29)5.
Calculate (0.29)5: Calculate (0.29)5. (0.29)5=0.29×0.29×0.29×0.29×0.29 This calculation gives us approximately 0.006408. Now we can calculate P(X=2): P(X=2)=21×0.5041×0.006408=0.0679057688.
Calculate Total Probability: Calculate the total probability for k=0, k=1, and k=2. The total probability that the Islanders will win at most two out of seven games is the sum of the probabilities for k=0, k=1, and k=2: P(X≤2)=P(X=0)+P(X=1)+P(X=2)P(X≤2)=0.0005741+0.00994049+0.0679057688P(X≤2)=0.0784203588 Round this to the nearest thousandth to get the final answer.
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