Question

Can someone please help me?

The Alpha Delta Phi Sorority raises money for the Ronald McDonald house by holding an annual "Roll for Ronald" race. Mary Lou Baker rides a bicycle and travels at twice the speed of Wayne Siegert, who is on rollerblades. Mary and Wayne begin the race at the same time and after 3 hours, Mary is 18 miles ahead of Wayne.
a. What is Wayne's speed?
b. What is Mary's speed?
(Please show me how to set up the equations.)

Answer 1

if wayne is travelling at x miles/hour then mary is travelling 2x miles per hour

so in 3 hours

mary travels 6x miles and wayne travels 3x miles

so the difference between the distance is 18 miles

6x - 3x = 18

so

3x = 18

you can find the value of x, and then work out the speed for wayne and mary