Subject: General Aptitude · Chapter: Time and Distance · Exam: 2007 · Marks: · Difficulty:
A person travels 285 km in 6 hours in two stages. In the first part of the journey, he travels by bus at the speed of 40 km per hour. In the second part of the journey, he travels by train at the speed of 55 km per hour. How much distance did he travel by train?
(a)145 km
(b)165 km
(c)185 km
(d)205 km
Answer
Answer (as printed): B
Explanation
Let the distance travelled by the train be $x \mathrm{km}$. Then, distance travelled by bus $=(285-x) \mathrm{km}$. $$\begin{aligned} & \therefore \quad\left(\frac{285-x}{40}\right)+\frac{x}{55}=6 \Leftrightarrow \frac{(285-x)}{8}+\frac{x}{11}=30 \\ & \Leftrightarrow \quad \frac{11(285-x)+8 x}{88}=30 \\ & \Leftrightarrow \quad 3135-11 x+8 x=2640 \Leftrightarrow 3 x=495 \Leftrightarrow x=165 . \end{aligned}$$ Hence, distance travelled by train = 165 km.