Starting at home, ishann traveled uphill to the grocery store for 12 minutes at just 15 mph. Then he traveled back home along the same path downhill at a speed of 30 mph. What is his average speed for the entire trip from home to the grocery store and back?

Trip uphill to the store:

distance = speed * time

= (15mph) * (12minutes/60 minutes per hour)

= (15mph) * (0.2 hours)

= 3 miles

trip downhill back home is along the same path

so the trip downhill was also equal to 3 miles.

So the the entire trip was a distance of 6 miles

3 miles uphill and 3 miles downhill.

So the average speed = (15mph uphill + 30mph downhill) / 2

= 45 mph/2

= 22.5 mpg

So the average speed of the entire trip uphill and downhill is 22.5 mph