1
Q:

# If Deepesh had walked 20 km/h faster he woulh have saved 1 hour in the distance of 60km. what is the usual speed of Deepesh?

 A) 100 B) 120 C) 150 D) None of these

Explanation:

Let the original speed  be x km/h, then

$\inline&space;\frac{600}{x}-\frac{600}{(X+20)}=1$

$\inline&space;\Rightarrow&space;600\left&space;(&space;\frac{x+20-x}{x(x+20)}&space;\right&space;)=1$

$\inline&space;\Rightarrow&space;\:&space;\:&space;x^{2}+120x-12000=0$

$\inline&space;\Rightarrow&space;\:&space;\:&space;(x-120)(x-100)=0$

$\inline&space;\Rightarrow&space;\:&space;\:&space;x=100&space;\:&space;\:&space;and\:&space;\:&space;x=120$

$\inline&space;\therefore$ original speed = 100km/h

Q:

Two motor bikes cover the same distance at the speed of 60 and 64 kmps respectively. Find the distance traveled by them if the slower bike takes 1 hour more than the faster bike ?

 A) 1102 km B) 1060 km C) 960 km D) 1250 km

Explanation:

60(x + 1) = 64x

X = 15

60 x 16 = 960 km

1 20
Q:

A man whose speed is 4.5 kmph in still water rows to a certain upstream point and back to the starting point in a river which flows at 1.5 kmph, find his average speed for the total journey ?

 A) 5 kmph B) 7 kmph C) 3 kmph D) 4 kmph

Explanation:

Speed of Man = 4.5 kmph
Speed of stream = 1.5 kmph
Speed in DownStream = 6 kmph
Speed in UpStream = 3 kmph
Average Speed = (2 x 6 x 3)/9 = 4 kmph.

1 13
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

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

1 44
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

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.

1 36
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

time t = $\inline \fn_jvn \small \frac{800x18}{60x5}$ = 48 sec.