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Q:

The speed of a car increases by 2 kms after every one hour. If the distance travelling in the first one hour was 35 kms. what was the total distance travelled in 12 hours?

A) 456 kms B) 482 kms
C) 552 kms D) 556 kms

Answer:   C) 552 kms

Explanation:

Total distance travelled in 12 hours    =(35+37+39+.....upto 12 terms)
This is an A.P with first term, a=35, number of terms,
n= 12,d=2.
Required distance    = 12/2[2 x 35+{12-1) x 2]
=6(70+23)
= 552 kms.

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.

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1 2
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 = 800x18/(60x5) = 48 sec.

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1 1
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.

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1 9
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.

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1 7
Q:

An express traveled at an average speed of 100 km/hr, stopping for 4 min after every 75 km. How long did it take to reach its destination 600 km from the starting point ?

A) 6 hrs 24 min B) 6 hrs
C) 7 hrs 21 min D) 6 hrs 28 min
 
Answer & Explanation Answer: D) 6 hrs 28 min

Explanation:

Time taken to cover 600 km = 600/100 = 6 hrs.

Number of stoppages = 600/75 - 1 = 7

Total time of stoppages = 4 x 7 = 28 min

Hence, total time taken = 6 hrs 28 min.

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