Selected MCQ

Current Question
A reservoir is 80 m × 60 m × 6.5 m. Time to fill at given rate is ____.
  • A. 26 hours
  • B. 42 hours
  • C. 52 hours
  • D. 65 hours
Correct Answer: C
Explanation:
Volume ÷ rate.
Related Question 1
The simple interest and true discount on a certain sum for a given time at a given rate are Rs. 85 and Rs. 80, respectively. Find the sum.
  • A. Rs. 1800
  • B. Rs. 1450
  • C. Rs. 1360
  • D. Rs. 6800
Correct Answer: C
Explanation:
Using the relation between SI and TD, the principal is Rs. 1360.
Related Question 2
Pipes A, B, C fill tank in 12, 15, 20 houRs. If A alone works, time required is ____.
  • A. 6 hrs
  • B. 6⅔ hrs
  • C. 7 hrs
  • D. 7½ hrs
Correct Answer: C
Explanation:
Based on the given combination.
Related Question 3
Pipes A, B, C fill tank in 12, 15, 20 houRs. Find time together.
  • A. 6 hours
  • B. 6⅔ hours
  • C. 7 hours
  • D. 7½ hours
Correct Answer: C
Explanation:
Combined rate method.
Related Question 4
Three pipes fill a tank in 6 houRs. After 2 hours, one is closed. Remaining time is ____.
  • A. 10
  • B. 12
  • C. 14
  • D. 16
Correct Answer: C
Explanation:
Work-rate adjustment.
Related Question 5
The simple interest on Rs. 49500 for 3 years is Rs. 17820. What is the compound interest on the same sum and time at the same rate?
  • A. Rs. 20043.94
  • B. Rs. 18654.81
  • C. Rs. 20264.46
  • D. Rs. 19612.41
Correct Answer: A
Explanation:
First, find the rate from SI, then apply the CI formula to get Rs. 20043.94.