Subject: General Aptitude · Chapter: Time and Work · Exam: 2006 · Marks: · Difficulty:
A does 20\% less work than B. If A can complete a piece of work in $7 \frac{1}{2}$ hours, then B can do it in
(a)5 hours
(b)$5 \frac{1}{2}$ hours
(c)6 hours
(d)$6 \frac{1}{2}$ hours
Answer
Answer (as printed): C
Explanation
Ratio of times taken by A and B = $100:80=5:4$. Suppose B takes $x$ hours to do the work. $5:4::\frac{15}{2}:x \Rightarrow x=\frac{4 \times \frac{15}{2}}{5} \Rightarrow x=6$ hours.
Explanation as extracted from the printed page; notation may be imperfect.