Zane and Cole started on a 55-km cycling trip at the same time. They cycled at the same speed for first 5 km. For the remaining 50 km, Zane cycled faster than Cole. He arrived at the finishing point 12 minutes before Cole who was 5 km behind him. Cole 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 Zane's average speed for the remaining 50 km of the trip in km/h?
(a)
60 min = 1 h
12 min =
1260 h =
15 Cole's average speed
= 5 ÷
15 = 25 km/h
Time that Cole took for the trip
= 55 ÷ 25
= 2
525 h
= 2
15 h
= 2 h 12 min
2 h 12 min before 08 25 is 06 13.
(b)
To find the time that Zane took for the remaining 50 km of the trip, we need to use the time that Cole took subtract that of the time taken for first 5 km and the time that Zane was faster than Cole.
Time that Zane took for the remaining 50 km of the trip
= 2
15 -
15 -
15 = 1
45 h
Zane's average speed
= 50 ÷ 1
45 = 27
79 km/h
Answer(s): (a) 06 13; (b) 27
79 km/h