A is 40% more efficient than B. If they together can finish a work in 10 days, in how many days can A alone finish it?
A. 15 days
B. 17(1/7) days
C. 14 days
D. 16(2/3) days
Answer: Option B
Solution (By JKSSB Mock Tests)
Let efficiency of B = 5, then efficiency of A = 7. Combined efficiency = 12 units/day. Total work = 10 * 12 = 120 units. Time taken by A alone = 120 / 7 = 17(1/7) days.
A can complete a piece of work in 12 days, and B can complete the same work in 24 days. If they work together, how many days will it take them to complete the work?
Explanation:
A's 1-day work = 1/12, B's 1-day work = 1/24. Combined 1-day work = 1/12 + 1/24 = 3/24 = 1/8. Therefore, they will complete the work together in 8 days.
Two pipes A and B can fill a cistern in 12 minutes and 15 minutes respectively. There is also a waste pipe C. If all three pipes are opened together, the cistern is full in 20 minutes. How long will C take to empty the full cistern?
Explanation:
Total capacity = LCM(12, 15, 20) = 60 units. Efficiency of A = 5, B = 4. Combined efficiency of A+B+C = 3. Efficiency of C = 3 - (5 + 4) = -6. Thus, C empties 6 units/minute. Time taken by C to empty the full cistern = 60 / 6 = 10 minutes.
No comments yet. Be the first to start the discussion!