# Time and Distance - Aptitude Questions and Answers - RejinpaulPlacement

43.
Two men start together to walk to a certain destination, one at 3 kmph and another at 3.75 kmph. The latter arrives half an hour before the former. The distance is:

Solution:   Let the distance be x km.

Then, x/3 - x/3.75 = 1/2
=> 2.5x - 2x = 3.75
=> x = 3.75/0.50 = 15/2 = 7.5 km
44.
If a person walks at 14 km/hr instead of 10 km/hr, he would have walked 20 km more. The actual distance travelled by him is: [R.R.B. 2000]

Solution:   Let the actual distance travelled be x km.

Then, x/10 = (x + 20) / 14
=> 14x = 10x + 200
=> 4x = 200
=> x = 50 km.
45.
In a flight of 600 km, an aircraft was slowed down due to bad whether. Its average speed for the trip was reduced by 200 km/hr and the time of flight increased by 30 minutes. The duration of the flight is : [M.A.T 2002]

Solution:   Let the duration of the flight be x hours.

Then, (600/x) - 600/(x + 1/2) = 200
=> (600/x) - 1200/(2x + 1) = 200
=> x (2x + 1) = 3
=> 2x2 + x - 3 = 0
=> (2x + 3) (x - 1) = 0
=> x = 1 hr. [neglecting the -ve value of x]
46.
It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio of the speed of the train to that of the car is: [M.B.A 2001]

Solution:   Let the speed of the train be x km/hr and that of the car be y km/hr.

Then, (120/x) + (480/y) = 8 or 1/x + 4/y = 1/15 ......... (i)
And, (200/x) + (400/y) = 25/3 or 1/x + 2/y = 1/24 .....(ii)

Solving (i) and (ii), we get x = 60 and y = 80

Ratio of speeds = 60 : 80 = 3 : 4
47.
A is twice as fast as B and B is thrice as fast as C is. The journey covered by C is 54 minutes will be covered by B in:

Solution:   Let C's speed = x km/hr.
Then, B's speed = 3x km/hr and A's speed = 6x km/hr.

Ratio of times taken = 1/6 : 1/3 : 1 = 1 : 2 : 6

If C takes 6 min, then B takes 2 min.
If C takes 54 min, then B takes [(2/6) * 54] min = 18 min.
48.
Two men starting from the same place walk at the rate of 5 kmph and 5.5 kmph respectively. What time will they take to be 8.5 km apart, if they walk in the same direction?