A person goes to his office at 1/3rd of the speed at which he returns from his office. If the average speed during the whole trip is 12 m /h . what is the speed of the person while he was going to his office?

Correct Answer: 120 km

Correct Answer: 60 kmph

Explanation:

Speed of tractor = 360/12 = 30 kmph

Speed of jeep = 250 x 30/100 = 75 kmph

But, given ratio of speed of car, jeep and tractor is 3 : 5 : 2

Speed of car = 3 x 75/5 = 45 kmph

 

Required, average speed of car and jeep = 75 + 45/2 = 60 kmph.

Correct Answer: 5 kmph

Explanation:

Let p be the speed of man in kmph

According to the given data in the question,

Distance travelled by bus in 10 min with 20 kmph == Distance travelled by man in 8 min with (20 + p) kmph in opposite direction

=> 20 x 10/60 = 8/60 (20 + p)

=> 200 = 160 + 8p

=> p = 40/8 = 5 kmph.

Correct Answer: 40

Explanation:

Let distance = x km and usual rate = y kmph.
Then, x/y - x/(y+3) = 40/60 --> 2y (y+3) = 9x ----- (i)
Also, x/(y-2) - x/y = 40/60 --> y(y-2) = 3x -------- (ii)
On dividing (i) by (ii), we get:

x = 40 km.

Correct Answer: 80 km

Explanation:

Let the total distance be 'x' km.

Time taken to cover remaining 40% of x distance is    t 1 = 40 × x 100 × 48

But given time taken to cover first 60% of x distance is    t 2 = t 1 + 20 60 h r s

  $$\begin{gathered} t 2 = 60 × x 100 × 48 \\ \end{gathered}$$

? 60 × x 100 × 48 = 40 × x 100 × 48 + 20 60

 x=80 km.

Correct Answer: 75 km/h , 100 km/h

Explanation:

Let Pele x km in 1 hour. so Maradona takes (2h-40min)=1 h 20 min to cover x km. Let speed of Maradona and Pele be M and P respectively than 

                            x =M x (4/3)  and x= P x 1

  => M/P = 3/4 

 Again       300 M = 300 P = 1

? 300 3 k - 300 4 k = 1 

 => k= 25

  M= 3k = 75 km/h   and   P= 4k = 100 km/h 

( Through options it is very easy to solve)

Correct Answer: 204 m

Explanation:

To find the minimum distance, we have to get the LCM of 75, 80, 85

Now, LCM of 75, 80, 85 = 5 x 15 x 16 x 17 = 20400

Hence, the minimum distance each should walk so that thay can cover the distance in complete steps = 20400 cms = 20400/100 = 204 mts.

Correct Answer: Option B

Explanation:

Man walked 6 km at 1.5 kmph, again he walked 8 km at speed of 2 kmph and 40 km at a speed of 8kmph
time taken indivisually:
=> 6/1.5 = 4 m
=> 8/2 = 4 m
=> 40/8 = 5 m

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Average speed of man= total distance/ total time
=> 54/13 =  4 2 13 kmph

Correct Answer: 8 hrs

Explanation:

Given speed of the bike after servicing = 55 kmph

Time taken for travelling some distance at 55 kmph = 5 hrs

Then, 

Distance = Speed x Time = 55 x 5 = 275 kms.

Now, 

Speed of the bike before servicing = 35 kmph

Distance = 275 kms

Now, Time = Distance/Speed = 275/35 = 7.85 hrs =~ 8 hrs.

Correct Answer: 60 kmph

Explanation:

Speed of lorry = 360 12 = 30 kmph

Speed of van = 250 100 x 30 = 75 kmph

Speed of bike = 3 5 x 75 = 45 kmph

Therefore, now required average speed of bike and van  = 75 + 45 2= 60 kmph.