Aptitude - Time and Distance - Discussion

Take difference of 14 and 10 is 4.

4 km/hr speed decrease= 20 km more he go.
4unit = 20,
1unit = 5,
Then 10 * 5 = 50 km actual distance covered by him.

The difference per hour is 14 - 10 = 4 km.
So, the time taken to travel 20 km is = 20/4 = 5 hours.
Now, the actual distance = 10 * 5 = 50 km.

Indirect proportion by chain rule.

X:X+20 10:14
Hence X/10 = X+20/14.
So, the answer x=50.

Here time is constant.

S, the o formula for time is Distance /Speed.
10/x = 14/x+200.
Equate this we will find:
10x + 200 = 14x,
4x = 200,
X = 50.

14km/hr - 10 km/hr = 4 km/hr(difference)
4km/hr - 20km,
10km/hr (?),
= 10*20/4.
= 50km.

He travels 4 km/hr extra in the other case.

So if he traveled 20 km more in that case then it means the time he took would be time= distance/speed = 20/4= 5 hours. So now that we know the time he took, we can find the actual distance he traveled.

Distance= speed* time= 10*5= 50 km.

Most people have the confusion that time is equal has not been stated equal in the question, Then, how can we equate the two entities based on the assuption that time is equal, right?


Let me explain;
if t=1st hour, distance=10...also, distance=14
t=2nd hour, distance=20...also distance=14+14=28
..
.
Similarly when t=5th hour, distance=50...distance=70
Now, the difference in respective distances =70-50=20
This means that the distance covered is 20 more in the 5th hour when speed is 14kmph instead of 10kmph.
This means, in the same time, the distance covered is different(i.e. 20km more->as stated in the question)
This proves that the time interval is the same irrespective of speed is different.
So, we equated the two statements since the time taken has to be the same. Hope you got it.

Instead of 10 kmph he is walking 14kmph which means he is walking 4 kmph more and totally he walks 20 km.

Hence, 20/4=5.

If we take this for 10 kmph then x it by 5 which means 5* 50= 50kmph.

Can anyone tell me whether we can solve it like this?

He travel 14kmph instead of 10kmph,
So,
14 - 10=4.

Walked 20km more(distance÷speed)=time.

20÷4=5.

Actual distance is 10 * 5=50km. (Distance=time*speed).

S=14km/hr d=20km

T=d/s, So, 14/20= 5hrs,

Now we have T=5hrs and s=10km/hr is the actual speed he needs to go.

S=10 T=5

Now, d= S x T.
=10*-5.
= 50 km.
That's all.