Answer:
a) P(X = 5) = 0.04397
b) The probability that X exceeds its mean by more than 1 standard deviation = P(z > 1) = 0.159
Step-by-step explanation:
a) This question can be solved using binomial distribution function formula
Using Binomial,
P(X = x) = ⁿCₓ pˣ qⁿ⁻ˣ
n = total number of sample spaces = number of refrigerators to be examined before getting 5 refrigerators with defective compressors = 6
x = Number of successes required = 5
p = probability of success = probability of examining a refrigerator with defective compressor out of the total 12 = 5/12 = 0.4167
q = probability of failure = probability of examining a refrigerator without defective compressor out of the total 12 = 1 - (5/12) = 7/12 = 0.5833
P(X = 5) = ⁶C₅ (0.4167)⁵ (0.5833)⁶⁻⁵
P(X = 5) = ⁶C₅ (0.4167)⁵ (0.5833) = 1(0.01256)(0.5833) = 0.04397
P(X = 5) = 0.04397
b) The probability that X exceeds its mean by more than 1 standard deviation represents Z-score of z > 1
Using the normal distribution tables,
P(z > 1) = 1 - P(z ≤ 1) = 1 - 0.841 = 0.159
Answer:
Step-by-step explanation:
3rd:9
4th:15
10th:51
Using the product rule, then (A) is the answer.
The percent of discount from when Mark bought it versus it's original price is 20%. I think
