Selected MCQ

Current Question
A question paper consists of five problems, each having three internal choices. In how many ways can a candidate attempt at least one problem?
  • A. 63
  • B. 511
  • C. 1023
  • D. 15
Correct Answer: C
Explanation:
Total ways = (3+1)⁵ − 1 = 1023.
Related Question 1
The sum of five numbers is 655. The average of the first two is 85. Find the sum of the last three.
  • A. 180
  • B. 170
  • C. 190
  • D. 175
Correct Answer: A
Explanation:
Subtract known sum.
Related Question 2
In a test with 4 MCQs, each having 5 choices, how many answer patterns are possible?
  • A. 19
  • B. 120
  • C. 625
  • D. 1024
Correct Answer: C
Explanation:
Total combinations = 5⁴ = 625.
Related Question 3
A question paper has 10 true/false questions. How many answer patterns are possible?
  • A. 20
  • B. 40
  • C. 512
  • D. 1024
Correct Answer: D
Explanation:
Each question has 2 choices ⇒ 2¹⁰ = 1024.
Related Question 4
Two automobiles 150 km apart move toward each other. Time to meet is ____.
  • A. 2.5 hr
  • B. 2 hr
  • C. 1.75 hr
  • D. 1.5 hr
Correct Answer: D
Explanation:
Relative speed method.
Related Question 5
Three years ago, the average age of 6 members was 19. Find the present age of a boy.
  • A. 1 year
  • B. 1.5 years
  • C. 2 years
  • D. 2.5 years
Correct Answer: A
Explanation:
Total age difference method.