Johnny's home is m miles from school. Johnny runs to school at a speed of 8 mph and then walks home from school at half that speed. How long does it take Johnny to run to school?
The time it takes Johnny to run to school can be found by dividing the distance by the speed: time = distance / speed.
Given that Johnny's speed is 8 mph, the time it takes him to run to school is: time = distance / 8.
However, the distance from Johnny's home to school is given as "m" miles, so the time to run to school is: time = m / 8.
So, it takes Johnny m / 8 hours to run to school.