Subject: General Aptitude · Chapter: Time and Work · Exam: · Marks: · Difficulty:
A, B and C can do a piece of work in 20, 30 and 60 days respectively. In how many days can A do the work if he is assisted by B and C on every third day?
(a)12 days
(b)15 days
(c)16 days
(d)18 days
Answer
Answer (as printed): B
Explanation
A’s 2 days’ work = × 2 = . 20 10 1 1 1 6 1 (A + B + C)’s 1 day’s work = + + = = . 20 30 60 60 10 1 1 1 Work done in 3 days = + = . 10 10 5 1 Now, work is done in 3 days. 5 ∴ Whole work will be done in (3 × 5) = 15 days. 1 1 1 43
Explanation as extracted from the printed page; notation may be imperfect.