New RBI Grade B 2025 Notification will come Soon! Enroll Here

    Question

    ‘A’ alone can complete a work in 18 days. ‘B’

    alone can complete the same work in 25 days. If ‘A’ and ‘B’ work together for 5 days, then the remaining work can be completed by ‘A’ alone in how many days?
    A 5.4 days Correct Answer Incorrect Answer
    B 6.4 days Correct Answer Incorrect Answer
    C 9.4 days Correct Answer Incorrect Answer
    D 8.4 days Correct Answer Incorrect Answer

    Solution

    Let the total amount of work = 450 units {LCM of 18 and 25} Then, efficiency of ‘A’ = 450/18 = 25 units/day Efficiency of ‘B’ = 450/25 = 18 units/day Combined efficiency of ‘A’ and ‘B’ = 25 + 18 = 43 units/day Work completed by ‘A’ and ‘B’ together in 5 days = 5 × 43 = 215 units Remaining work = 450 – 215 = 235 units Time taken by ‘A’ alone to complete the remaining work = 235/25 = 9.4 days

    Practice Next

    Relevant for Exams: