Zane and Jeremy started on a 35-km cycling trip at the same time. They cycled at the same speed for first 5 km. For the remaining 30 km, Zane cycled faster than Jeremy. He arrived at the finishing point 20 minutes before Jeremy who was 5 km behind him. Jeremy did not change his speed throughout and completed it at 08 30.
- At what time did the trip begin? Give the answer in 12-hour format.
- What was Zane's average speed for the remaining 30 km of the trip in km/h?
(a)
60 min = 1 h
20 min =
2060 h =
13 Jeremy's average speed
= 5 ÷
13 = 15 km/h
Time that Jeremy took for the trip
= 35 ÷ 15
= 2
515 h
= 2
13 h
= 2 h 20 min
2 h 20 min before 08 30 is 06 10.
(b)
To find the time that Zane took for the remaining 30 km of the trip, we need to use the time that Jeremy took subtract that of the time taken for first 5 km and the time that Zane was faster than Jeremy.
Time that Zane took for the remaining 30 km of the trip
= 2
13 -
13 -
13 = 1
23 h
Zane's average speed
= 30 ÷ 1
23 = 18 km/h
Answer(s): (a) 06 10; (b) 18 km/h