Chapter 3, 4 and 5 Quiz

Which Excel function returns the value of 𝑋 for the 95th percentile, given 𝜇 = 100, 𝜎 = 15? A. =NORM.S.INV(0.95) B. =NORM.INV(0.95, 100, 15) C. =PERCENTILE(100, 0.95) D. =NORM.DIST(0.95, 100, 15, TRUE) E. =STANDARDIZE(100, 15, 0.95)

If λ = 3 for a Poisson distribution, what is P(X = 0)? a) 1 b) 0 c) e^-3 d) 3e^-3 e) (3^0 * e^-3)/0!

Which of the following is a discrete random variable? A. The number of students in a class B. Height of a person C. Temperature during the day D. Distance walked in a week E. Blood pressure readings

Which Excel function gives the cumulative probability for 𝑋 = 72, 𝜇 = 65, 𝜎 = 8? A. =NORM.S.DIST(72, TRUE) B. =NORM.DIST(72, 65, 8, TRUE) C. =NORM.INV(72, 65, 8) D. =STANDARDIZE(72, 65, 8) E. =Z.TEST(72, 65, 8)

How many 3-digit numbers can be formed using digits 1 to 5 without repetition?a) 60 b) 125 c) 20 d) 100 e) 10

What is the Z-score for 𝑋 = 90, 𝜇 = 70, 𝜎 = 10? A. 1 B. -2 C. 2 D. 0 E. 20

What is the probability of a continuous random variable taking on an exact value? A. 1 B. Depends on the distribution C. 0 D. 0.5 E. 100%

Which of the following scenarios is best modelled by a Binomial distribution? A.The time it takes to finish a race B. The number of cars passing a traffic light between 8–9AM C. The number of times a fair coin lands on heads in 10 flips

If test scores are normally distributed with 𝜇 = 50, 𝜎 = 5, what is the Z-score for a score of 60? A. -2 B. 1.5 C. 2 D. 0 E. 1

Which statement best describes 𝑋 ∼ 𝑁 ( 50 , 16 )? A. Mean = 16, SD = 50 B. Mean = 16, Variance = 50 C. Mean = 50, SD = 16 D. Mean = 50, Variance = 16 E. Mean = 4, SD = 50

What is the probability of drawing an ace from a standard deck of cards using classical definition?a) 1/4 b) 4/52 c) 1/13 d) 1/2 e) 13/52

When can the Poisson distribution approximate the binomial?a) n large, p small b) p = 0.5 c) p close to 1 d) n small, p large e) p = 0

What is the mean of X if X = {1, 2, 3, 4} and P(X) = {0.1, 0.2, 0.3, 0.4}?a) 2.5 b) 3.0 c) 3.1 d) 2.8 e) 2.9

What defines a binomial experiment?a) Continuous outcomes b) More than two outcomes c) Trials are not independent d) Two possible outcomes e) Unequal probabilities

Which Z-score corresponds to the 95th percentile in a standard normal distribution? A. 1.645 B. 1.96 C. 0.95 D. 2.58 E. 0.645

Which of the following is an example of a discrete random variable?a) Height b) Weight c) Number of students in a class d) Distance e) Age

If a die is rolled once, what is the probability of getting an even number?a) 1/6 b) 1/2 c) 2/3 d) 3/6 e) 1/3

A fair coin is tossed 5 times. What is the probability of getting exactly 3 heads?a) 5/16 b) 0.3125 c) 0.25 d) 0.5 e) 1/8

In an experiment of tossing a coin 100 times, heads appeared 43 times. What is the empirical probability of heads?a) 0.5 b) 43% c) 0.43 d) 0.57 e) 43/2

A question mentions “an average of 4 errors per page” and asks for the probability of getting exactly 2 errors on a page. What type of distribution should you use? A. Normal B. Binomial C. Exponential D. Uniform E. Poisson

What is the number of ways to choose 3 students out of 8?a) 24 b) 336 c) 56 d) 72 e) 168

Which Excel function returns the Z-score for 𝑋 = 72, 𝜇 = 65, 𝜎 = 8? A. =Z.TEST(72, 65, 8) B. =NORM.DIST(72, 65, 8, TRUE) C. =STANDARDIZE(72, 65, 8) D. =NORM.INV(72, 65, 8) E. =NORM.S.INV(0.72)

What is the Poisson distribution used to model?a) Fixed number of trials b) Rare events over time c) Replacement sampling d) Venn diagram logic e) Uniform distributions

A population consists of 10 red balls and 5 green balls. If 4 are selected without replacement, what distribution is used?a) Binomial b) Normal c) Hypergeometric d) Poisson e) Exponential

If P(A) = 0.3 and P(B) = 0.6 and A and B are mutually exclusive, what is P(A or B)?a) 0.18 b) 0.9 c) 0.3 d) 0.6 e) 1.2