Aptitude - Time and Distance - Discussion

The question is asked to find out the distance traveled by the person, and its clearly written he traveled 20km more so we equate it as (x+20) as the distance traveled by him and then when we get the value of X to be 50km. Why it is not added by 20km to get final answer as 70km ?

Kinnari's explanation is simple and good.

Note: That in both speed Time will be same so

for speed 10km/hr speed=distance/time
10 =x/time1
for speed 14km/hr 14 =(x+20)/time2

: Note time will be same so we equate these two equations respect with time

time1 = time2
time1 = x/10
time2 = (x+20)/14
(X/10)=(X+20)/14
we solve this to obation right answer

@Ilesh method is best one.

The persons speed of walking is 14km/hr.
He should have walked 10km/hr.
If he had gone with the speed of 10km/hr then he would have walked more den 20km/hr.
So,We are supposed to imagine if he had walked 10km/hr speed then what would be his actual speed.
So,we assume that let the distance be X km.


Then, the formula comes into picture i.e. speed=distance/time

So , as we are supposed to find as per the expectation if he had walked 10km/hr :
we take 10km/hr as his walking speed.
Distance is we are supposed to find more than 20
i.e. 20+X.
time is what the person actually doing .In reality the person is walking at 14km/hr.

So,in short with respect to person's capacity i.e. 14km/hr we can find the exact answer.
and therefore

Another formula for 10km/hr is :
time =distance by speed
i.e. time=X/10

time= X / 10 becomes the 1st equation....
time= (X + 20 ) / 14 becomes second equation....
from the above 2 eqns :
(X / 10 ) = (( X + 20 ) / 14)
then solve the further equation ....
Hope u got it :)

As time is same in both the case. Therefore distance is directly proportional to speed. Let distance is x.

x directly proportional to 10km/hr.
So, x/10 directly proportional to 1 km/hr.
And (x/10) *14 directly proportional to 14 km/hr.
And (x/10) *14 is the total distance covered in 2nd case which x+20.
So just compare both the distance i.e.
(x/10) *14 = x+20. You will get x=50. Answer.

still confusion guys

How you getting this (x+20) /14.

Ilesh method is good procedure than others because in question there is no clarity that the time is same.

Ilesh logical thinking sweet and simlpe...