38% of adults favor the use of unmanned drones by police agencies. Twelve U.S. adults are randomly selected. Find the probability that the number of U.S. adults who favor the use of unmanned drones

Question

38% of adults favor the use of unmanned drones by police agencies. Twelve U.S. adults are randomly selected. Find the probability that the number of U.S. adults who favor the use of unmanned drones by police agencies is (a) exactly three, (b) at least four, (c) less than eight.

A. P(3)

B. P(x≥4)

C. P(x<8)

Answer 1

This can be solved using the binomial distribution.

The number of trials, n = 12, probability of success (favor the use of unmanned drones) = 0.038, probability of failure (do not favor the use of unmanned drones) = 1 - 0.036 = 0.62

The trails

1. are randomly selected
2. are independent
3. have the same probability of success.
4. You can use Desmos to work out you problem: Open Desmos, click on the keyboard, the functions. Under dist. select binomialdist and enter 12, 0.38 in the parentheses.

For A. P(X=3), select the CDF Box, and enter 3 in the Min. and 3 in the Max., to give you a Probability of 0.163.

For B. P(x≥4), enter 4 in the Min Box, and 12 in the Max. Box to give you a probability of 0.729.

For C. P(x<8), enter 0 in the Min Box, and 7 in the Max. box, to give you a probability of 0.958