1.

A train can travel 50% faster than a car. Both start from point A at the same time and reach point B 75 km away from A at the same time. On the way, however, the train lost about 12.5 minutes while stopping at the stations. The speed of the car is (a) 100 km/hr (b) 110 km/hr (c) 120 km/hr (d) 130 km/hr

Answer»

(c) 120 km/hr

Let the speed of the car be x km/hr 

Then, speed of the train = \(\frac{150x}{100}\) km/hr = \(\frac{3x}{2}\) km/hr

Time taken by car to reach point B = \(\frac{75}{x}\) hrs

Time taken by train to reach point B = \(\frac{75}{\frac{3}{2}x}\) hrs

Given, \(\frac{75}{x}\) - \(\frac{75}{\frac{3}{2}x}\) = \(\frac{12.5}{60}\)

⇒ \(\frac{75}{x}\) - \(\frac{50}{x}\) = \(\frac{125}{10\times60}\) = \(\frac{5}{24}\) ⇒ \(\frac{25}{x}\) = \(\frac{5}{24}\)

⇒ x = \(\frac{25\times24}{5}\) = 120 km/hr.



Discussion

No Comment Found

Related InterviewSolutions