Hello!

I am having some trouble on one of my homework problems. I can't figure out what the equation should be. Any help you can give will be wonderful!!

A racer can cycle around a circular loop at the rate of 2 revolutions per hour. Another cyclist can cycle the same loop at the rate of 5 revolutions per hour. If they start at the same time (t=0), at what first time are they farthest apart?

Thanks!