Fabian and Ethan started on a 45-km cycling trip at the same time. They cycled at the same speed for first 10 km. For the remaining 35 km, Fabian cycled faster than Ethan. He arrived at the finishing point 30 minutes before Ethan who was 10 km behind him. Ethan did not change his speed throughout and completed it at 08 25.
- At what time did the trip begin? Give the answer in 12-hour format.
- What was Fabian's average speed for the remaining 35 km of the trip in km/h?
(a)
60 min = 1 h
30 min =
3060 h =
12 Ethan's average speed
= 10 ÷
12 = 20 km/h
Time that Ethan took for the trip
= 45 ÷ 20
= 2
520 h
= 2
14 h
= 2 h 15 min
2 h 15 min before 08 25 is 06 10.
(b)
To find the time that Fabian took for the remaining 35 km of the trip, we need to use the time that Ethan took subtract that of the time taken for first 10 km and the time that Fabian was faster than Ethan.
Time that Fabian took for the remaining 35 km of the trip
= 2
14 -
12 -
12 = 1
14 h
Fabian's average speed
= 35 ÷ 1
14 = 28 km/h
Answer(s): (a) 06 10; (b) 28 km/h