Subject: General Aptitude · Chapter: Time and Work · Exam: 2007 · Marks: · Difficulty:
A can do a piece of work in 14 days which B can do in 21 days. They begin together but 3 days before the completion of the work, A leaves off. The total number of days to complete the work is
(a)$6 \frac{3}{5}$
(b)$8 \frac{1}{2}$
(c)$10 \frac{1}{5}$
(d)$13 \frac{1}{2}$
Answer
Answer (as printed): C
Explanation
B’s 3 days’ work = × 3 = . 21 7 1 6 Remaining work = 1 − = . 7 7 549 1 1 5 (A + B)’s 1 day’s work = + = . 14 21 42 5 Now, work is done by A and B in 1 day. 42 6 42 6 36 ∴ work is done by A and B in × = days. 7 5 7 5 36 1 Hence, total time taken = 3 + days = 10 days. 5 5 1 1 1 13
Explanation as extracted from the printed page; notation may be imperfect.