CAT 1993QA Question 47

Relative SpeedEasy
Passage / Data

Directions for next 3 questions:

Q started to move from point B towards point A exactly an hour after P started from A in the opposite direction. Q’s speed was twice that of P. When P had covered one-sixth of the distance between the points A and B, Q had also covered the same distance.

A ship leave on a long voyage. When it is 18 miles from the shore, a seaplane, whose speed is ten times that of the ship, is sent to deliver mail. How far from the shore does the seaplane catch up with the ship?

Answer & solution

  • A

    24 miles

  • B

    25 miles

  • C

    22 miles

  • 20 miles

Solution

The separation between the ship and the seaplane is 18 miles. 

Since the two are travelling in the same direction, the relative speed would be 9 times the speed of the ship (If speed of ship is x miles/hour, speed of the seaplane would be 10x and 10x – x = 9x). 

Hence, to catch up with the ship, the seaplane would take 189x=2x hours. 

Now, the ship covers x miles in an hour, so in 2x hours it would cover 2 miles. 

So when the seaplane catches up with the ship, it would be 18 + 2 = 20 miles from the shore.

Hence, option (d).

CAT 1993 QA Q47: A ship leave on a long voyage. When it is 18 miles from the shore, a seaplane, whose speed is ten times that o — Solution | TheCATExam