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 walk to school?
To find out how long it takes Johnny to walk to school, we need to divide the distance of his home from school by his walking speed.
The distance from Johnny's home to school is m miles, and his walking speed is 8 mph.
The time it takes Johnny to walk to school is therefore:
m miles / (8 mph) = m/8 hours.
Therefore, it takes Johnny m/8 hours to walk to school.