Answer: Speed of walker and biker will be 16.67 miles per hour and 25 miles per hour respectively.
Step-by-step explanation:
Let the speed of a walker be x
Let the speed of a biker be 1.5x
They are moving in the same direction,
so, their Relative speed will be

Time taken = 1.5 hours
Distance between them = 12.5 miles
As we know the formula for "Distance":

Hence, Speed of walker be 16.67 miles per hour
Speed of biker be
