Question

Spencer and Dustin both leave the Internet cafe at the same time, but in opposite directions. If Dustin travels 5 mph faster than Spencer's and after 8 hours they are 264 miles apart, how fast is each traveling?

Answer 1

Let us say that:

x = speed of Spencer

x + 5 = speed of Dustin

Therefore:

8 x + 8 (x + 5) = 264

8 x + 8 x + 40 = 264

16 x = 224

x = 14 mph = speed of Spencer

So speed of Dustin is:

x + 5 = 19 mph = speed of Dustin