Question

If Satyajit Ray cycles at 10 km/hr, then he arrives at a certain place at 1 p.m. If he cycles at 15 km/hr, he will arrive at the same place at 11 a.m. At what speed must Satyajit Ray cycle to get there at noon?

1. 6 km/h
2. 9 km/h
3. 15 km/h
4. 12 km/h
5.

Answer 1

Correct Answer - Option 4 : 12 km/h

Calculation:

⇒ Let’s suppose that the time taken by Satyajit Ray at 10 km/h to cover the distance by 1 pm = t h

⇒ Now at speed of 15 km/h the time taken = (t - 2) h

⇒ Now the distance covered is the same so we can say that

⇒ 10(t) = 15(t - 2)

⇒ t = 6

⇒ Therefore, the distance covered will be = 10 x 6 = 60

⇒ Therefore, the speed at which Satyajit Ray has to travel to reach the place at noon = 60/(t - 1) = 60/5 = 12 km/h