It's a father-son thing
A father takes his son from his school on a scooter everyday at uniform speed. But on a particular day, the son leaves for home at 7km/h before an hour of the closing time of the school. The father starts from home as usually, takes son on the way to home (without wasting time). If they arrive 24 minutes earlier than usual what's the speed of the scooter in km/h?