A student walks from his home to school at a speed of 4 km/h and reaches 15 minutes late. If he increases his speed to 6 km/h, he reaches 5 minutes early. What is the distance (in km) from his home to school?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 4 km.
Let distance = d km
Time at 4 km/h =
Time at 6 km/h =
Late by 15 min and early by 5 min
difference = 20 min = hr
⇒ − =
⇒ =
⇒ =
⇒ d = 4 km