Aptitude - Time and Distance - Discussion

So much complicated answers who said time is not given.

The man travels with different speeds but for the same time.

Let's assume that time as x.

Now for the same time, the distance travelled is different because speed is different.

Now Distance = Speed*Time.

For the same time, distance travelled will be greater for higher speed i.e. 14 kmph and the difference of distance is 20 km.

So 14x-10x = 20 (since 20 km more). x = 5 i.e. Time = 5 hrs.

So actual distance is 10*x = 10*5 = 50 kmph.

The answer comes in two steps I explained to make it easier.

Can you please explain me the question in detail?

What is the meaning of actual here? Either 14 km/hr or 10 km/hr.

Easy way:

Actually travelled 10 kmph.

If travelled 14 kmph then he would have travelled 20 kmph more.

14-10 = 4.

Means 20/4 = 5.

Then actually he travelled 10 kmph.

So, 10*5 = 50 answer.

Here in this question both the times are equal. So we use s1/d1 = s2/d2.

Therefore: 10/x = 14/x+20.

10x+200 = 14x.

4x = 200.

x = 50.

Time is considered as equal in both cases because of its average speed. Look over the question again. Speed is 14kmph & 10 kmph. It means 14 km travelled in one hour and 10 km travelled in one hour. So the time in both cases is the same.

Speed increase 14 - 10 = 4 kmph and so that distance increase 20 km.
When distance increases 4 km then time is 1 hour.
When distance increases 1 km then time is 1/4 hour.
When distance increases 20 km then time is 20/4 hour or 5 hours.

So, he journeyed 5 hours in 10 kmph.
So, distance is 5 * 10 = 50 hour.

Note : This technique is more useful for quick calculation.

We know,

Time = Distance/Speed.

Let's take original distance is X.

Given,
Speed is 10km/1hr and 14km/1hr.

Now we can write,
1hr = X distance/10 speed --> (1).

Similarly,
1hr = (X + 20) distance/14 speed --> (2).

Now, put the value of (1) in (2).
We will get,

X/10 = (X + 20)/14.
14X = 10X + 200.
4X = 200.
X = 50.

@Manish Nair.

Thanks for your solution.

I did not understand the concept.