Time And Distance

How much time did X take to reach the destination?
I.	The ratio between the speed of X and Y is 3 : 4.
II.	Y takes 36 minutes to reach the same destination.

A:

I alone sufficient while II alone not sufficient to answer

B:

II alone sufficient while I alone not sufficient to answer

C:

Either I or II alone sufficient to answer

D:

Both I and II are not sufficient to answer

Answer: E

Since ratio of speed of X : Y is 3 : 4, then ratio of time will be 4 : 3.

I. If Y takes 3 min, then X takes 4 min.

II. If Y takes 36 min, then X takes		4	x 36	min	= 48 min.
		3

Thus, I and II together give the answer.

Correct answer is (E).

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Two cars pass each other in opposite direction. How long would they take to be 500 km apart?
I.	The sum of their speeds is 135 km/hr.
II.	The difference of their speed is 25 km/hr.

A:

I alone sufficient while II alone not sufficient to answer

B:

II alone sufficient while I alone not sufficient to answer

C:

Either I or II alone sufficient to answer

D:

Both I and II are not sufficient to answer

Answer: A

I gives, relative speed = 135 km/hr.

Time taken =	500	hrs.
	135

II does not give the relative speed.

I alone gives the answer and II is irrelevant.

Correct answer is (A).

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The towns A, B and C are on a straight line. Town C is between A and B. The distance from A to B is 100 km. How far is A from C?
I.	The distance from A to B is 25% more than the distance from C to B.
II.	The distance from A to C is of the distance C to B.

A:

I alone sufficient while II alone not sufficient to answer

B:

II alone sufficient while I alone not sufficient to answer

C:

Either I or II alone sufficient to answer

D:

Both I and II are not sufficient to answer

Answer: C

.__________.______________________________________.
A     x    C            (100 - x)                 B

Let AC = x km. Then, CB = (100 -x) km.

I. AB = 125% of CB

100 =	125	x (100 - x)
	100

100 - x =	100 x 100	= 80
	125

x = 20 km.

AC = 20 km.

Thus, I alone gives the answer.

II. AC =	1	CB
	4

x =	1	(100 - x)
	4

5x = 100

x = 20.

AC = 20 km.

Thus, II alone gives the answer.

Correct answer is (C).

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Two towns are connected by railway. Can you find the distance between them?
I.	The speed of the mail train is 12 km/hr more than that of an express train.
II.	A mail train takes 40 minutes less than an express train to cover the distance.

A:

I alone sufficient while II alone not sufficient to answer

B:

II alone sufficient while I alone not sufficient to answer

C:

Either I or II alone sufficient to answer

D:

Both I and II are not sufficient to answer

Answer: D

Let the distance between the two stations be x km.

I. Then, speed of the mail train = (y + 12) km/hr.

II.	x	-	x	=	40	.
	y		(y + 12)		60

Thus, even I and II together do not give x.

Correct answer is (D).

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A man covered a certain distance at some speed. Had he moved 3 kmph faster, he would have taken 40 minutes less. If he had moved 2 kmph slower, he would have taken 40 minutes more. The distance (in km) is:

A:

35

B:

36	2
	3

C:

37	1
	2

D:

40

Answer: D

Let distance = x km and usual rate = y kmph.

Then,	x	-	x	=	40	2y(y + 3) = 9x ....(i)
	y		y + 3		60

And,	x	-	x	=	40	y(y - 2) = 3x ....(ii)
	y -2		y		60

On dividing (i) by (ii), we get: x = 40.

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Questions for: Time And Distance