not sure about a word problem

Question

Henry can ride his horse at 4mph to get to the battlefield on time. If he stops for and hour to make a speech to his troops, he must ride at 5mph for the whole trip to get to the battlefield on time. How far is it to the battlefield?

Answer 1

distance = rate*time

 

If he doesn't stop:

 

distance = (4 mph)*time

 

If he stops for an hour:

 

distance = (5 mph)*(time - 1 hour)

 

Since the distance is the same in either case:

 

4*time = 5*(time-1)

4*time = 5*time - 5

 

5 hours = time

 

distance = (4 mph)*time = (4 mph)*(5 hours) = 20 miles