Maths
posted by Tammy .
Two cyclists depart from the same point. One travels due East at 18km/hr while the other travels NorthWest at 20km/hr. How long will it be before they are 80km apart?

80^2=t^2(20^2+18^2)
solve for time t. 
Wonderful, thank you

Two cyclists leave a park and ride in opposite directions, one averaging 5 mph and the other 10 mph. If they have twoway radios with a 10mile range, for how many minutes will they remain in radio contact?