K drives 280 miles same time as D drives 260miles. K averages 4 miles per hour faster than Dave find there rates

Question

idk how to set  the equation

Answer 1

distance = rate x time

 

280 = (r+4) x t  <--- 4 mph faster

 

280 = r x t + 4 x t

 

260 = r x t

 

280 = 260 + 4 x t

 

20 = 4 x t

 

t=5

 

So they travel 5 hours

 

280 miles in 5 hours is 280/5 = 56 mph

260 miles in 5 hours is 260/5 = 52 mph.

 

4 mph fast shows these results are correct