Uniform Motion
November 8th, 2022
Two mountain bikers started from the ranger station in Rocky Mountain National Park traveling in the same direction on Trail Ridge Road. The first biker left 1 hour earlier than the second and traveled 10 miles/hour. The second biker left later and traveled 15 miles/hour. By 4:00 pm, the second biker had passed the first and was 5 miles ahead of the first biker. What time did the first biker leave the ranger station?
Please show how you arrived at the answer.