Selected MCQ

Current Question
Three men walk around a circular track of 11 km. Find a time for them to meet again.
  • A. 11 hours
  • B. 12 hours
  • C. 220 hours
  • D. 22 hours
Correct Answer: A
Explanation:
LCM of time intervals.
Related Question 1
A man walks around a circular field once per hour. At what time will he complete a round if he starts at 7:42 a.m.?
  • A. 7:42 a.m.
  • B. 7:48 a.m.
  • C. 8:10 a.m.
  • D. 8:30 a.m.
Correct Answer: A
Explanation:
One full round takes exactly 1 hour, so the time remains the same format.
Related Question 2
One root of Equation x² − 12x + a = 0 is three times the other. Find a.
  • A. 29
  • B. 27
  • C. 28
  • D. 7
Correct Answer: B
Explanation:
Roots x, 3x → sum = 4x = 12 → x = 3 → a = 27.
Related Question 3
A, B, and C start running around a circular track. When do they meet again?
  • A. 26 min 18 sec
  • B. 42 min 36 sec
  • C. 45 min
  • D. 46 min 12 sec
Correct Answer: D
Explanation:
LCM of times.
Related Question 4
A tank is filled in 5 hours by three pipes, A, B, and C. If C is twice as fast as B, find the total time.
  • A. 20 hrs
  • B. 25 hrs
  • C. 35 hrs
  • D. Cannot be determined
Correct Answer: C
Explanation:
Solve rate equations.
Related Question 5
Three pipes fill a tank. The first two together take 15 houRs. Find total time.
  • A. 6 hrs
  • B. 10 hrs
  • C. 15 hrs
  • D. 30 hrs
Correct Answer: C
Explanation:
Combined rate leads to 15 houRs.