Question 174808
A bus and a cyclist leave a school at 8 AM and head for a stadium 90 miles away. The rate of the bus is three times the rate of the cyclist. The cyclist arrives 4 hours after the bus. What is the equation? Find the rate of the bus. 
--------------
Bus DATA:
distance = 90 miles; rate = 3x mph ; time = d/r = 90/3x = 30/x hours
----------------
Cyclist DATA:
distance = 90 miles; rate = x mph ; time = d/r = 90/x hours
-----------------
Equation:
cyclist time - bus time = 4 hrs.
90/x - 30/x = 4
90 - 30 = 4x
4x = 60
x = 15 mph (rate of the cyclist)
3x = 45 mph (rate of the bus)
==================================
Cheers,
Stan H.