The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 kms in 4 hrs, then the speed of the first train is: [I.M.T 2002]
A train travels at an average of 50 miles per hour for 2 1/2 hours and then travels at a speed of 70 miles per hour for 1 1/2 hours. How far did the train travel in the entire 4 hours? [IGNOU 2003]
A man in a train notices that he can count 21 telephone posts in one minute. If they are known to be 50 metres apart, then at what speed is the train travelling?
Sound is said to travel in air at about 1100 feet per second. A man hears the axe striking the tree, 11/5 seconds after he sees it strike the tree. How far is the man from the wood chopper? [M.B.A 2002]
An express train travelled at an average speed of 100 km/hr, stopping for 3 minutes after every 75 km. How long did it take to reach its destination600 km from the starting point? [M.A.T 2003]
A certain distance is covered by a cyclist at a certain speed. If a jogger covers half the distance in double the time, the ratio of the speed of the jogger to that of the cyclist is:
A motor car starts with the speed of 70 km/hr with its speed increasing every two hours by 10 kmph. In how many hours will it cover 345 kms? [Bank P.O. 2003]
Answer & Solution
Answer: c) 4 1/2 hrs
Solution: Distance covered in first 2 hours = (70 * 2) km = 140 km. Distance covered in next 2 hours = (80 * 2) km = 160 km. Remaining distance = 345 - (140 + 160) = 45 km. Speed in the fifth hour = 90 km/hr. Time taken to cover 45 km = (45/90) hr = 1/2 hr. Total time taken = (2 + 2 + 1/2) = 4 1/2 hrs.