Selected MCQ

Current Question
Out of 10 persons, 4 are graduates. Probability that at least one is graduate when 3 are chosen is ____.
  • A. 1/6
  • B. 5/8
  • C. 3/8
  • D. 5/6
Correct Answer: D
Explanation:
Use the complement method → 1 − (6C3/10C3).
Related Question 1
In a party of 5 couples, 5 people are chosen. What is the probability of at least two couples?
  • A. 5/21
  • B. 5/14
  • C. 9/14
  • D. 16/21
Correct Answer: A
Explanation:
Using combinations and the complement method gives 5/21.
Related Question 2
The probability of a lottery ticket being a winning ticket is 0.2. If 4 tickets are bought, what is the probability of at least one win?
  • A. 0.4869
  • B. 0.5904
  • C. 0.6234
  • D. 0.5834
Correct Answer: B
Explanation:
Probability = 1 − (0.8)⁴ = 0.5904.
Related Question 3
12 people draw lots. Probability that one specific host has dinner is ____.
  • A. One
  • B. Zero
  • C. Three
  • D. Cannot be
Correct Answer: D
Explanation:
Insufficient clarity.
Related Question 4
Three persons invest Rs. 9000. Second invests Rs. 3000. Profit share of first is ____.
  • A. Rs. 2400
  • B. Rs. 3600
  • C. Rs. 2850
  • D. Rs. 2000
Correct Answer: A
Explanation:
Profit shares are proportional to investment.
Related Question 5
Three dice are thrown. Probability that no two show same number is ____.
  • A. 7/12
  • B. 5/9
  • C. 1/36
  • D. 5/12
Correct Answer: B
Explanation:
Favorable = 120 → 120/216 = 5/9.