Question

A man walking at a speed of 45 km/hr reaches station 10 minute late. Next time he increases his speed by 15 km/hr but still late by 5 minutes. Find the distance of station from his house

Answer 1

Answer: The distance of station from his house is 15 km.

Step-by-step explanation:

We know,

speed= distance/time

=> time= distance/speed

Let d be the total distance from his house to station.

Here, we have two case as follow:

Case 1 when his speed is 45 km/h, he reaches 10 minutes late.

Case 2 when he increases his speed by km/hr, he reaches 5 minutes late.

Speed of the man in the first case= 45 km/h ( given)

Speed of the man in the second case= 45+15= 60 km/h

And

Time difference in both cases= 10-5= 5 min= 5/60= 1/12 h

Now, according to the question

d/45 - d/60= 1/12 ( because the time difference in both case= 1/12 h)

Multiplying the above equation with the lcm of 45, 60, and 12, i.e., 180

d/45*180 - d/60*180= 1/12*180

4d - 3d= 15

d= 15 km