1.
A train passes a station platform in 36 seconds and a man standing on the platform in 20 seconds. If the speed of the train is 54 km/hr ,what is the length of the platform?
Answer: Option 'B'
Given, time taken by train to pass the man = 20 sec
Speed of the train = 54 km/hr
---> Converting into meter/sec
=> Speed of train =54 × (5/18) m/sec = 15 m/sec
W.K.T: Speed of train = Length of train/ Time taken by train to pass the man
=> 15 =Length of train / 20
=>Length of train = 15 × 20
=>Length of train = 300 metre.
Given,A train passes a station platform in 36 seconds.
=>Speed of train = (Length of train + Length of platform) / Time taken by train to pass the platform
=> 15 = (300 +Length of platform) / 36
=> 15 × 36 = (300+Length of platform)
=> 540 =300+Length of platform
=> 540 - 300 =Length of platform
Thus,Length of platform = 240 meter.
2.
Avinash covers a distance of 8km in 50 minutes. If he covers 3km distance in 2/5th of time then, What speed should he maintain to cover the remaining distance in the remaining time?
Answer: Option 'C'
Total distance = 8 Km
Total time = 50 Km
Time taken to cover the distence of 3 Km = 50*2/5 = 20 min = 1/3 hours
Remaining distance = 8 - 3 = 5 Km
Required speed = 5/1/3 = 15 Kmph
3.
In a covering a certain distance the speed of A and B are in the ratio of 6: 9, A takes 20 min more, than B to reach the destination. The time taken by A to reach the destination is:
Answer: Option 'A'
Let the speed of A and B are 6x Kmph
and 9x Kmph respectively,
Let the total distance to travel = y Km
y/6x - y/9x = 1/3
y/x(1/18 = 1/3
y = 6x
Required time = 6x/6x = 1 hour
4.
If a man walks 24 Km at 8 Kmph, he will be late by 25min. if he walks 12 Kmph, how early the fixed time Will he reach?
Answer: Option 'D'
Time taken to cover 24 Km at the speed of 8 Kmph = 24/8 = 3 hours
Thus, right time was 2 hours 35 mintes
Now, time taken to cover 20 Km at the speed as 12 Kmph = 2 hours
Required time = 2 hours 35 minutes - 2 hours
= 35 minutes
5.
A goods train runs at the speed of 72 km/hr and crosses a 250 m long platform in 26 seconds .What is the length of the goods train?
Answer: Option 'A'
270 m