Akhil after travelling 50 km meets Raju who suggests him to go slower. He then proceeds at ¾ of his former speed and arrives at his destination 35 minutes late. Had the meeting occurred 24 km further Akhil would have reached its destination 25 minutes late. What is the initial speed of Akhil?

Correct Answer: 1400

Explanation:

Given the ratio of the circumference of front wheel  is 40 inches and back wheel is 70 inches. 

 

Distance covered = Circumference of the wheel × No. of Revolutions made by the wheel

 

If n is the number of revolutions made by back wheel, the number of revolutions made by front wheel is n+15

 

Distance covered by both the wheels is the same

 

i.e, 40*(n+15)=70n

 

 n=20 

 

 

 

                Front wheel      :      Back Wheel 

 

 Circumference       40      :      70 

 

 Revolutions           35      :      20

 

 

 

Distance covered  :  40×35 = 70×20 = 1400 inches.

Correct Answer: 70 kms

Explanation:

Let the time taken by train be 't' hrs.

Then,

40 t = 35 t + 15 60

40t = 35t + 35/4

t = 7/4 hrs

Therefore, Required length of the total journey d = s x t

= 40 x 7/4

= 70 kms.

Correct Answer: 4.18

Explanation:

Distance to be covered =  ?D = 40 ? km 

Relative speed of bikers = 16 + 14 = 30 kmph.

 

Now,  t i m e = d i s tan c e s p e e d =   40 ? 30 = 4.18 hrs.

Correct Answer: 11

Explanation:

Do not assume that AB and C are on a straight line. Make a diagram with A and B marked 5 miles apart. Draw a circle centered on B, with radius 6. C could be anywhere on this circle. The minimum distance will be 1, and maximum 11

Correct Answer: 4 kms

Explanation:

Let the actual distance be t kms

Now, According to the data,

 

$$\begin{gathered} 5 t + 8 60 = 6 t \\ = > 5 60 t + 8 60 = 6 t \\ = > 60 t + 8 = 72 t \\ = > 8 = 12 t \\ = > t = 8 / 12 = 2 / 3 hrs \end{gathered}$$

 

Now, the total distance = 6t = 6 x 2/3 = 2 x 2 = 4 kms.

Correct Answer: None of these

Explanation:

Let t be the time after Kajol starts, when she meets Ajay, then 

               t = 300/(x+y) 

 This should be less than 2.5 or (x+y)>120 

Since       y= 3x/2  =>  y > 72

This (y>72) is greater than 67.5 km/h and hence Shahrukh will always overtake Ajay before he meets Kajol.

Correct Answer: 27 sec

Explanation:

Time taken to meet for the first time anywhere on the track

= length of the track / relative speed

= 300 / (15 + 25)5/18 = 300x 18 / 40 x 5 = 27 seconds.

Correct Answer: 99

Explanation:

Let, Distance between A and B = d

 

Distance travelled by P while it meets Q = d + 11

 

Distance travelled by Q while it meets P = d ? 11

 

Distance travelled by Q while it meets R = d + 9

 

Distance travelled by R while it meets Q = d ? 9

 

Here the ratio of speeds of P & Q => SP : SQ = d + 11 : d ? 11

 

The ratio of speeds of Q & R => SQ : SR = d + 9 : d ? 9

 

But given Ratio of speeds of P & R => P : R = 3 : 2

  S P S R = S P S Q x S Q S R = d + 11 d + 9 d - 11 d - 9

 

=>  d + 11 d + 9 d - 11 d - 9 = 3/2

 

=>  d = 1, 99

 

=> d = 99 satisfies.

 

Therefore, Distance between A and B = 99

Correct Answer: 17 hours

Explanation:

In this type of questions we need to get the relative speed between them,
The relative speed of the boys = 5.5kmph ? 5kmph
= 0.5 kmph

Distance between them is 8.5 km
Time = Distance/Speed
Time= 8.5km / 0.5 kmph = 17 hrs

Correct Answer: bm/60c

Explanation:

Substitute sensible numbers and work out the problem. Then change the numbers back to letters. For example if the machine puts 6 caps on bottles in 2 minutes, it will put 6 /2 caps on per minute, or (6 /2) x 60 caps per hour. Putting letters back this is 60c/m.If you divide the required number of caps (b) by the caps per hour you will get time taken in hours. This gives bm/60c