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Suppose that it is believed that 40% of adults have a company pension. If 100 adults are surveyed. What is the probability of finding a sample, above 30 adults but no more than 45 adults, having a pension?

a. 0.0207
b. 0.8254
c. 0.04899
d. 0.8461

User Paskos
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1 Answer

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Final answer:

To find the probability of finding a sample of adults with a company pension, you can use the binomial distribution formula and calculate the probabilities for the given range of successes. Using the cumulative distribution function, the probability of finding a sample with a pension above 30 adults but no more than 45 adults is 0.04899.

Step-by-step explanation:

To find the probability of finding a sample of adults with a pension, we can use the binomial distribution. The formula for finding the probability of a range of successes in a binomial distribution is:

P(X=k) = C(n, k) * p^k * (1-p)^(n-k),

where n is the sample size, k is the number of successes, C(n, k) is the number of combinations of n items taken k at a time, and p is the probability of success for each individual. In this case, n = 100, k ranges from 30 to 45, and p = 0.4. To find the probability of the given range, we need to sum the probabilities for each individual k value using the formula above. By using cumulative distribution function (cdf), we can calculate this probability.

Using a calculator or statistical software, we find that the probability of finding a sample with a pension above 30 adults but no more than 45 adults is 0.04899.

User Nifle
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