Free Probability Distributions MCQs with Answers

132 Probability Distributions MCQs from Statistics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.

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132 questions · page 4 of 7

  • A. All probability distribution
  • B. The hypergeometric distribution
  • C. The binomial distribution
  • D. The Poisson distribution

Explanation: For a Poisson distribution with parameter λ, both the mean and variance equal λ.

Correct answer: The Poisson distribution
  • A. Poisson dist
  • B. Standard dist
  • C. Normal dist
  • D. Hyper-geometric distribution

Explanation: With sufficiently large n and a suitable p, the binomial distribution is approximated by the normal distribution through the central limit…

Correct answer: Normal dist
  • A. Become more positively skewed
  • B. Become more negatively skewed
  • C. Become symmetrical
  • D. All of the above.

Explanation: The binomial skewness is determined by q − p: at p = 0.50 it is symmetric, but as p falls below 0.50, q becomes larger and the…

Correct answer: Become more positively skewed
  • A. 6
  • B. 1
  • C. 2/5
  • D. None of these

Explanation: The mean of a binomial distribution is np. Thus, np = 10 × 3/5 = 6.

Correct answer: 6
  • A. Probability remains constant for all the trials.
  • B. Probability changes from trial to trial
  • C. Successive trial are dependent
  • D. Both (b) & (c) but not (a)

Explanation: In a hypergeometric distribution, sampling is without replacement, so the success probability changes after each draw and successive…

Correct answer: Both (b) & (c) but not (a)
  • A. P > q
  • B. P = 1/2
  • C. Probability of success & probability of failure are equal
  • D. Both (b) & (c) but not (a)

Explanation: A binomial distribution is symmetric when the success and failure probabilities are equal, so p = q = 1/2.

Correct answer: Both (b) & (c) but not (a)
  • A. X
  • B. n x p
  • C. n(1 - 1)
  • D. ∑fx/∑f

Explanation: For a binomial distribution with n trials and success probability p, the expected number of successes is np.

Correct answer: n x p
  • A. {nx}px qn-x
  • B. {nx}px(1 - P)x-n
  • C. nCxpnqnx
  • D. {nx}p(1 - P)x

Explanation: The binomial probability for exactly x successes is C(n,x)p^xq^(n−x), where q = 1 − p.

Correct answer: {nx}px qn-x
  • A. n, q
  • B. n, p, q
  • C. q, p
  • D. n, p

Explanation: A binomial distribution has two independent parameters: n, the fixed number of trials, and p, the probability of success.

Correct answer: n, p
  • A. Times
  • B. Fixed
  • C. Expansion
  • D. Trial

Explanation: A defining condition of the binomial experiment is that it is repeated a fixed number n of times.

Correct answer: Fixed
  • A. 60
  • B. 30
  • C. 20
  • D. 40

Explanation: The binomial mean is np, so the mean is 400 × 0.1 = 40. This makes option (d) correct.

Correct answer: 40
  • A. 1 to n
  • B. 0 to n
  • C. 1 to ∞
  • D. 0 to ∞

Explanation: For a binomial variable, the number of successes can be as low as 0 and as high as all n trials, so its range is 0 to n.

Correct answer: 0 to n
  • A. p > q
  • B. P = q
  • C. p < q
  • D. P/q

Explanation: A binomial distribution is positively skewed when successes are less likely than failures, meaning p<q.

Correct answer: p < q
  • A. n; fixed number of times
  • B. a large number times
  • C. n; where n < 0
  • D. n = 100

Explanation: A binomial experiment consists of n independent trials, where n is a fixed positive integer.

Correct answer: n; fixed number of times
  • A. Dependent
  • B. Independent
  • C. Linear
  • D. Equal

Explanation: The formulas mean=np and variance=npq apply when the n Bernoulli trials are independent and have the same success probability p.

Correct answer: Independent
  • A. Pq
  • B. nP
  • C. xm
  • D. Non of these

Explanation: The binomial mean equals the expected number of successes, calculated as the number of trials multiplied by the success probability…

Correct answer: nP
  • A. Equal to variance
  • B. Less than variance
  • C. Greater than varince
  • D. None of these

Explanation: The binomial mean is np and its variance is npq. Since 0<q<1 in the standard case, np is greater than npq, so the mean is greater than the…

Correct answer: Greater than varince
  • A. 4
  • B. 3
  • C. 2
  • D. 6

Explanation: A binomial distribution is determined by two parameters: n, the number of trials, and p, the probability of success on each trial.

Correct answer: 2
  • A. Dependent
  • B. Independent
  • C. Equally Likely
  • D. Mutually exclusive
  • E. Non

Explanation: The trials in a binomial experiment are independent, meaning the outcome of one trial does not change the probability of success on…

Correct answer: Independent
  • A. 10
  • B. 12
  • C. 2.1
  • D. 21
  • E. None

Explanation: For a binomial variable, variance is npq, where q = 1 - p. Here, npq = 10(0.3)(0.7) = 2.1.

Correct answer: 2.1