8
Q:

Akash leaves mumbai at 6 am and reaches Bangalore  at  10 am . Prakash leaves Bangalore at 8 am and reaches Mumbai at 11:30 am. At what time do they cross each other?

A) 10 am B) 8:32 am
C) 8:56 am D) 9:20 am

Answer:   C) 8:56 am

Explanation:

Time taken by Akash = 4 h

Time taken by Prakash = 3.5 h

For your convenience take the product of times taken by both as a distance.

Then  the distance = 14km

Since, Akash covers half of the distance  in 2 hours(i.e at 8 am)

Now, the rest half (i.e 7 km) will be coverd by both prakash and akash

Time taken by them = 7/7.5 = 56 min

Thus , they will cross each other at  8 : 56am.

Q:

The current of a stream at 1 kmph. A motor boat goes 35 km upstream and back to the starting point in 12 hours. The speed of the motor boat in still water is ?

A) 8 kmph B) 6 kmph
C) 7.5 kmph D) 5.5 kmph
 
Answer & Explanation Answer: B) 6 kmph

Explanation:

Speed of the stream = 1
Motor boat speed in still water be = x kmph
Down Stream = x + 1 kmph
Up Stream = x - 1 kmph
[35/(x + 1)] + [35/(x - 1)] = 12
x = 6 kmph

Report Error

View Answer Workspace Report Error Discuss

1 24
Q:

A Bus is running at 9/10 of its own speed reached a place in 22 hours. How much time could be saved if the bus would run at its own speed ?

A) 1.5 hrs B) 1.7 hrs
C) 2.2 hrs D) 3.5 hrs
 
Answer & Explanation Answer: C) 2.2 hrs

Explanation:

Let the original Speed be "s" kmph
And the usual time be "t" hrs
Given that if the bus is running at 9s/10 kmph the time is 22 hrs
=> [9s/10] x 22 = t x s
=> 99/5 = t
=> t = 19.8 hrs

 

Hence, if bus runs at its own speed, the time saved = 22 - 19.8 = 2.2 hrs.

Report Error

View Answer Workspace Report Error Discuss

1 30
Q:

How many seconds will a 800 meter long train moving with a speed of 63 km/hr take to cross a man walking with a speed of 3 km/hr in the direction of the train ?

A) 48 B) 52
C) 38 D) 42
 
Answer & Explanation Answer: A) 48

Explanation:

Here distance d = 800 mts
speed s = 63 - 3 = 60 kmph = 60 x 5/18 m/s
time t = = 48 sec.

Report Error

View Answer Workspace Report Error Discuss

1 24
Q:

P is faster than Q. P and Q each walk 24 km. The sum of their speeds is 7 km/hr and the sum of times taken by them is 14 hours. Then, P's speed is equal to ?

A) 3 km/hr B) 4 km/hr
C) 5 km/hr D) 6 km/hr
 
Answer & Explanation Answer: B) 4 km/hr

Explanation:

Let P's speed = x km/hr. Then, Q's speed = (7 - x) km/ hr.

So, 24/x + 24/(7 - x) = 14

- 98x + 168 = 0

(x - 3)(x - 4) = 0 => x = 3 or 4.

Since, P is faster than Q,

so P's speed = 4 km/hr and Q's speed = 3 km/hr.

Report Error

View Answer Workspace Report Error Discuss

1 19
Q:

A man walks at a speed of 2 km/hr and runs at a speed of 6 km/hr. How much time will the man require to cover a distance of 20 1/2 km, if he completes half of the distance, i.e., (10 1/4) km on foot and the other half by running ?

A) 12.4 hrs B) 11.9 hrs
C) 10.7 hrs D) 9.9 hrs
 
Answer & Explanation Answer: B) 11.9 hrs

Explanation:

We know that

Time = Distance/speed
Required time = (10 1/4)/2 + (10 1/4)/6
= 41/8 + 41/6
= 287/24 = 11.9 hours.

Report Error

View Answer Workspace Report Error Discuss

1 16