Starting from his house one day, a student walk at a speed of 2 kmph and reaches his school 10 minutes late. Next he increased his speed by 1 kmph and reaches the school 10 minutes early. How far is the school from his house?	Choose the correct choice from the following answers:
A) 1km
B) 2km
C) 3km
D) 4km
E) 5km
Let the distance be x km   Difference in timings = 20 min = 20/60 = 1/3 hr   x/2-x/3 = 1/3   x = 2km   Answer is 2km
<result>B</result>
Starting from his house one day, a student walk at a speed of 2 kmph and reaches his school 10 minutes late. Next he increased his speed by 1 kmph and reaches the school 10 minutes early. How far is the school from his house?