Question
A multiple choice test has five choices. Therefore the probability of getting the correct answer by guessing is 0.2. The test has six questions. Use the binomial formula with n = 6 and p = 0.2 to (a) Determine probability of getting two questions correct.
(b)Determine probability of getting between one and four (inclusive) correct
(b)Determine probability of getting between one and four (inclusive) correct
Answers
PsyDAG
If the events are independent, the probability of both/all events occurring is determined by multiplying the probabilities of the individual events.
2 correct = .2^2 * .8^4 = ?
1 correct = .2 * .8^5 = ?
3 correct = .2^3 * .8^3 = ?
4 correct = .2^4 * .8^2 = ?
Either-or probabilities are found by adding the individual probabilities, so add the probabilities you have found.
2 correct = .2^2 * .8^4 = ?
1 correct = .2 * .8^5 = ?
3 correct = .2^3 * .8^3 = ?
4 correct = .2^4 * .8^2 = ?
Either-or probabilities are found by adding the individual probabilities, so add the probabilities you have found.
Heidi
A unbiased die is thrown seven times. Find the probability of throwing at least five six's.