WBCS Mains 2018 Official Paper-VI

A is twice as good a workman as B. A and B together complete a piece of work in $28$ days. In how many days will A alone do the same piece of work?

A boatman can row a boat downstream and upstream at $13\text{kmph}$ and $9\text{kmph}$ respectively. What will be the speed of the boat in still water (in $\text{kmph}$)?

Ram was asked to find $\frac{7}{8}$ of a fraction but he mistakenly divided the fraction by $\frac{7}{8}$. As a result, the difference between the answers was $\frac{75}{784}$. What should be Ram’s correct answer?

If a man runs $6\text{kmph}$ from his house, he misses the train at the station by $8\text{ minutes}$. If he runs at $10\text{kmph}$, he reaches the station $7\text{ minutes}$ earlier than the departure of the train. What is the distance of the station from his house (in $\text{km}$)?

The area of a circle is $2464\text{ square meters}$. What will be its circumference?