Free Probability MCQs with Answers

41 Probability 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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41 questions · page 4 of 5

31. If P(B/A)= 0.25 and P(A∩B) = 0.2 then P(A) will equal to _______________?

Moderate
  • A. 0.05
  • B. 0.75
  • C. 0.8
  • D. 0.45

Explanation: Using P(B|A)=P(A∩B)/P(A), substitute 0.25=0.2/P(A). Rearranging gives P(A)=0.2/0.25=0.8.

Correct answer: 0.8

32. A coin is so weighted that P (T) = 2P(H) then P(H) is _______________?

Moderate
  • A. 1/2
  • B. 1
  • C. 2/3
  • D. 1/3

Explanation: Since the two possible outcomes exhaust the probability, P(H)+P(T)=1. Substituting P(T)=2P(H) gives 3P(H)=1, so P(H)=1/3.

Correct answer: 1/3

33. The probability of getting exactly two heads when two balanced coins are toss once_________________?

Moderate
  • A. 1/4
  • B. 2/4
  • C. 3/4
  • D. 4/4

Explanation: With two balanced coins, the equally likely outcomes are HH, HT, TH and TT. Exactly two heads occurs only as HH, giving a probability of 1/4.

Correct answer: 1/4

34. The probability of drawing a diamond card out of 52 cards is ______________?

Moderate
  • A. 13/52
  • B. 1/2
  • C. 4/52
  • D. 0

Explanation: A standard deck has 13 diamond cards among 52 cards. Therefore, the probability of drawing a diamond is 13/52, which simplifies to 1/4.

Correct answer: 13/52

35. All experiments have _______ properties in common?

Moderate
  • A. Four
  • B. Three
  • C. Two
  • D. One

Explanation: A probability experiment has two key features: its possible outcomes are specified, but the particular outcome cannot be predicted with certainty before the experiment. Thus, the expected number is two.

Correct answer: Two

36. A experiment repeated number of time one by one is called _________________?

Moderate
  • A. Random
  • B. Raw data
  • C. Introduce
  • D. Specified

Explanation: An experiment whose outcome is uncertain and which can be repeated under similar conditions is called a random experiment. The other choices do not name a type of experiment.

Correct answer: Random

37. A list of sample _________ is called sample space?

Moderate
  • A. Events
  • B. Subset
  • C. Piont
  • D. Distinct

Explanation: A sample space is the set or list of all possible sample points, or outcomes, of an experiment. “Piont” is a misspelling of “point,” but it identifies the intended answer.

Correct answer: Piont

38. when a three die rolled the sample space consists of _____________?

Moderate
  • A. 6 outcomes
  • B. 24 outcomes
  • C. 216 outcomes
  • D. Non of these

Explanation: Each of the three dice has 6 possible outcomes, and the choices combine independently. The total number of ordered outcomes is 6×6×6=6^3=216.

Correct answer: 216 outcomes

39. The probability of a save event is equal to _________________?

Moderate
  • A. Two
  • B. Three
  • C. Four
  • D. One

Explanation: A sure event always occurs, so its probability is 1. The word “save” is evidently intended to be “sure.”

Correct answer: One

40. The basic random numbers are ________________?

Moderate
  • A. 0 and 1
  • B. 0,1,2,............9
  • C. 1,2,3....10
  • D. None of these

Explanation: Basic random digits are the ten digits from 0 through 9, commonly used to construct random numbers for sampling and simulation.

Correct answer: 0,1,2,............9