Subject: General Aptitude · Chapter: Time and Work · Exam: 2009 · Marks: · Difficulty:
A and B together can complete a work in 12 days, B and C together can complete the same work in 8 days and A and C together can complete it in 16 days. In total, how many days do A, B and C together take to complete the same work?
(a)$3 \frac{5}{12}$
(b)$3 \frac{9}{13}$
(c)$7 \frac{5}{12}$
(d)$7 \frac{5}{13}$
(e)None of these
Answer
Answer (as printed): D
Explanation
(A + B)’s 1 day’s work = ; 12 1 (B + C)’s 1 day’s work = ; 8 1 (A + C)’s 1 day’s work = . 16 Adding, we get: 2 (A + B + C)’s 1 day’s work 1 1 1 13 = + + = . 12 8 16 48 13 ∴ (A + B + C)’s 1 day’s work = . 96 So, A, B and C together can complete the work in 96 5 =7 days. 13 13 1
Explanation as extracted from the printed page; notation may be imperfect.