Tim and Peter 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, Tim cycled faster than Peter. He arrived at the finishing point 30 minutes before Peter who was 10 km behind him. Peter 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 Tim's average speed for the remaining 35 km of the trip in km/h?
(a)
60 min = 1 h
30 min =
3060 h =
12 Peter's average speed
= 10 ÷
12 = 20 km/h
Time that Peter 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 Tim took for the remaining 35 km of the trip, we need to use the time that Peter took subtract that of the time taken for first 10 km and the time that Tim was faster than Peter.
Time that Tim took for the remaining 35 km of the trip
= 2
14 -
12 -
12 = 1
14 h
Tim's average speed
= 35 ÷ 1
14 = 28 km/h
Answer(s): (a) 06 10; (b) 28 km/h