Problem 4RE

In Exercises, assume that 40% of the population has brown eyes (based on data from Dr. P. Sorita at Indiana University).

Brown Eyes When randomly selecting 600 people, the probability of exactly 239 people with brown eyes is P(239) = 0.0331. Also, P(239 or fewer) = 0.484. Which of those two probabilities is relevant for determining whether 239 is an unusually low number of people with brown eyes? Is 239 an unusually low number of people with brown eyes?

Answer:

Step 1 of 2

Here, P(239 or fewer) = 0.484 is greater than 0.05

Thus, 239 or fewer is not an unusually low number of people with brown eyes.

P(239) = 0.0331 is unusually low number.

Thus, 239 is unusually low number of people with brown eyes.

Given, n = 600, p = 40% = 0.4, q = 1 - p = 0.6