📢 Too many exams? Don’t know which one suits you best? Book Your Free Expert 👉 call Now!
  • google app store apple app store
    • ✖

      Question

      Worker A can build a wall alone in 30 days. When A and B

      work together, they can complete the wall in 16 days. If B starts building the wall alone and works for 20 days before leaving, how many additional days will A need to finish the remaining work alone?
      A 10 days Correct Answer Incorrect Answer
      B 11 days Correct Answer Incorrect Answer
      C 12.5 days Correct Answer Incorrect Answer
      D 14.5 days Correct Answer Incorrect Answer
      E None of these Correct Answer Incorrect Answer

      Solution

      Let the total work to be done to build the wall = L.C.M of 30 and 16 = 240 units
      Then, efficiency of ‘A’ = 240 ÷ 30 = 8 units/day
      Combined efficiency of ‘A’ and ‘B’ = 240 ÷ 16 = 15 units/day
      So, efficiency of ‘B’ = 15 – 8 = 7 units/day
      Work done by ‘B’ in 20 days = 7 × 20 = 140 units
      Remaining work = 240 – 140 = 100 units
      Time taken by ‘A’ to complete the remaining work = 100 ÷ 8 = 12.5 days

      Practice Next
      More Time and work Questions

      Relevant for Exams:

      ask-question