Q103
ArithmeticSpeed, Time & Distance
Two trains, one from Howrah to Patna and other from Patna to Howrah, start simultaneouly. After they meet, the trains reach their destinations after 9 hours and 16 hours respectively. The ratio of their speeds is
- a.2 : 3
- b.4 : 3
- c.6 : 7
- d.9 : 16
Answer: (B) 4 : 3
For two trains starting together towards each other, speed ratio = $\sqrt{t_2} : \sqrt{t_1}$, where $t_1$, $t_2$ are their times after meeting. Here that is $\sqrt{16} : \sqrt{9}$ = 4 : 3. 9 : 16 is the ratio of the times, not of the speeds.