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 8 of 14

71. If p= 0.1 and n = 400 then mean _______________?

Moderate
  • 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

72. Binomial distribution ranges from _______________?

Moderate
  • 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

73. Binomial distribution is positively skewed when ______________?

Moderate
  • 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. When p=q it is symmetrical, while p>q produces negative skewness.

Correct answer: p < q

74. In binomial experiment, the experiment is repeated ______________?

Moderate
  • 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. The number of repetitions is not necessarily large and cannot be negative.

Correct answer: n; fixed number of times

75. In binomial distribution with ________ trials mean is np and variance is npq?

Moderate
  • 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. Dependence would generally change the variance formula.

Correct answer: Independent

76. Mean of the binomial distribution is ______________?

Moderate
  • 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: E(X)=np.

Correct answer: nP

77. The mean of a binomial distribution is always:____________________?

Moderate
  • 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 variance.

Correct answer: Greater than varince

78. Binomial distribution has _______ parameter?

Moderate
  • 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. Thus, it has two parameters.

Correct answer: 2

79. Successive trials in binomial distribution are:__________________?

Moderate
  • 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 another. They must also have the same success probability.

Correct answer: Independent

80. A random variable X has binomial distribution with n = 10 and p = 0.3 then variance of X is:_____________________?

Moderate
  • 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