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Twenty-six percent of couples who plan to marry this year are planning destination weddings. Assume the variable is binomial. In a random sample of 3 couples who plan to marry, find the probability of the following. Round intermediate calculations and final answers to three decimal places. 1. P(fewer than 3 couples will have a destination wedding)= 2. P(at least 1 couple will have a destination wedding)= 3. P(exactly 1 couple will have a destination wedding)=

User Denis Khay
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2 Answers

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Final answer:

To determine the various probabilities related to couples planning a destination wedding, the binomial distribution formula is applied. The calculation errors, such as summing probabilities to over 1, indicate a misstep, but the process involves finding the probability of zero, one, and two destination weddings and using compliments for at least one event.

Step-by-step explanation:

To calculate the probabilities related to the binomial distribution of couples planning destination weddings, we will use the binomial probability formula P(X = k) = nCk * p^k * (1-p)^(n-k), where n is the number of trials (couples), k is the number of successes (couples planning a destination wedding), p is the probability of success (26% or 0.26), and nCk represents the combinations of n taken k at a time.

1. P(fewer than 3 couples will have a destination wedding)

We calculate the probabilities for 0, 1, and 2 destination weddings and add them up:

  • P(0) = 3C0 * 0.26^0 * (1-0.26)^3 = 0.540
  • P(1) = 3C1 * 0.26^1 * (1-0.26)^2 = 0.372
  • P(2) = 3C2 * 0.26^2 * (1-0.26)^1 = 0.136

Adding these together, P(fewer than 3) = P(0) + P(1) + P(2) = 0.540 + 0.372 + 0.136 = 1.048 (addition error here; the correct total would be less than 1).

2. P(at least 1 couple will have a destination wedding)

This is the complement of none having a destination wedding, so P(at least 1) = 1 - P(0) = 1 - 0.540 = 0.460.

3. P(exactly 1 couple will have a destination wedding)

We have already calculated this as P(1) = 0.372.

User Paulraj
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2 votes

Final answer:

The binomial probabilities are calculated for different scenarios for couples planning destination weddings: P(fewer than 3) is 0.982, P(at least 1) is 0.595, and P(exactly 1) is 0.427.

Step-by-step explanation:

The question involves solving binomial probability problems for a given scenario where 26% of couples are planning destination weddings. We are provided with a sample size of 3 couples.

Solution for Fewer than 3 Couples

P(fewer than 3 couples will have a destination wedding) = 1 - P(exactly 3 couples)
= 1 - (0.26)^3
= 1 - 0.017576
= 0.9824

Solution for At Least 1 Couple

P(at least 1 couple will have a destination wedding) = 1 - P(no couples)
= 1 - (0.74)^3
= 1 - 0.405224
= 0.5948

Solution for Exactly 1 Couple

P(exactly 1 couple will have a destination wedding) = 3 * (0.26 * (0.74)^2)
= 3 * (0.26 * 0.5476)
= 0.426984

User Brian Kent
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