Posted by leena on .
To travel 175 miles, it takes Sue, riding a moped, 4 hours less time than it takes Doreen to travel 66 miles riding a bicycle. Sue travels 19 miles per hour faster than Doreen. Find the times and rates of both girls.

Math 
PsyDAG,
Let Doreen's speed = x and Sue's = x + 19.
Let y  4 = Doreen's time and y = Sue's time
Speed = distance/time
x = 175/(y4) (Doreen)
x + 19 = 66/y (Sue)
Substitute the value of x from the first equation into the second and solve.
I hope this helps. Thanks for asking.