Fabian and Jenson started on a 50-km cycling trip at the same time. They cycled at the same speed for first 5 km. For the remaining 45 km, Fabian cycled faster than Jenson. He arrived at the finishing point 20 minutes before Jenson who was 5 km behind him. Jenson did not change his speed throughout and completed it at 09 30.
- At what time did the trip begin? Give the answer in 12-hour format.
- What was Fabian's average speed for the remaining 45 km of the trip in km/h?
(a)
60 min = 1 h
20 min =
2060 h =
13 Jenson's average speed
= 5 ÷
13 = 15 km/h
Time that Jenson took for the trip
= 50 ÷ 15
= 3
515 h
= 3
13 h
= 3 h 20 min
3 h 20 min before 09 30 is 06 10.
(b)
To find the time that Fabian took for the remaining 45 km of the trip, we need to use the time that Jenson took subtract that of the time taken for first 5 km and the time that Fabian was faster than Jenson.
Time that Fabian took for the remaining 45 km of the trip
= 3
13 -
13 -
13 = 2
23 h
Fabian's average speed
= 45 ÷ 2
23 = 16
78 km/h
Answer(s): (a) 06 10; (b) 16
78 km/h