Question

Handedness A psychologist needs 12 left-handed subjects for an experiment, and she interviews 15 potential subjects. About 10% of the population is left-handed. What is the probability that exactly 12 of the potential subjects are left-handed?

Answer 1

To calculate the probability of exactly 12 out of 15 potential subjects being left-handed, we can use the binomial probability formula.

Step-by-step explanation:

To calculate the probability of exactly 12 out of 15 potential subjects being left-handed when about 10% of the population is left-handed, we can use the binomial probability formula. The formula is: P(x) = C(n, x) * p^x * (1-p)^(n-x), where P(x) is the probability of x successes, C(n, x) is the number of ways to choose x successes from n possibilities, p is the probability of success, and (1-p) is the probability of failure.

In this case, n = 15, x = 12, and p = 0.1. Plugging in these values, we get: P(12) = C(15, 12) * 0.1^12 * (1-0.1)^(15-12). Calculating this gives us the probability that exactly 12 of the potential subjects are left-handed.