Alright, lets get started.
Suppose first bicyclist speed is = x mph
As given in question, second one is 4 mph slower than first, hence
Speed of second bicyclist is = (x-4) mph
They both travels 3 hrs so,
distance covered by first bicyclist :
[tex] distance = speed* time [/tex]
[tex] d1 = 3x [/tex]
distance covered by second bicyclist :
[tex] d2= 3 (x-4) [/tex]
4 miles were still left after 3 hrs of driving.
It means they covered 88 - 4 = 84 miles together
[tex] d1 + d2 = 84 [/tex]
[tex] 3x + 3 (x-4) = 84 [/tex]
[tex] 3x + 3x - 12 = 84 [/tex]
Adding 12 in both sides
[tex] 6x - 12 + 12 = 84 + 12 [/tex]
[tex] 6x = 96 [/tex]
Dividing 6 in both sides
[tex] \frac{6x}{6}= \frac{96}{6} [/tex]
[tex] x = 16 [/tex]
Means speed of first bicyclist = 16 mph
Speed of second bicyclist = [tex] 16 - 4 = 12 [/tex] mph
Hence speed of both bicyclist are 16 mph and 12 mph. : Answer
Hope it will help :)
