how to find the rate

Question

Two buses leave a station at the same time and travel in opposite directions. One bus travels
9/mih slower than the other. If the two buses are
702mi apart after 6 hours, what is the rate of each bus?

Answer 1

distance = rate*time

 

702 miles = rate*(6 hours)

 

117 mph = rate

 

The two buses are moving away from one another at a net speed of 117 mph.  Let the speed of the first bus be x mph.  The other is moving at 9 mph less, so its speed is x-9 mph:

 

x + (x-9) = 117 mph

2x - 9 = 117 mph

2x = 126 mph

 

x = 63 mph

 

The other bus is going x-9 = 63-9 = 54 mph.