City U and City V are 420 km apart. At 5.32 p.m., Julian is travelling at a uniform speed left City U for City V while Peter set off from City V to City U along the same road at a uniform speed, which was 10 km/h slower than that of Julian. The two met at 8.32 p.m.
- Find the speed of Julian.
- If Peter continued to travel at the same speed, how long would it take for him to reach his destination after the two met? Express your answer in mixed number.
(a)
Time taken for Julian and Peter to travel from 5.32 p.m. to 8.32 p.m. = 3 h
Average speed of Julian and Peter
= 420 ÷ 3
= 140 km/h
Julian's speed
= (140 + 10) ÷ 2
= 150 ÷ 2
= 75 km/h
(b)
Peter's speed
= 75 - 10
= 65 km/h
Distance that Peter travelled in 3 h
= 3 x 65
= 195 km
Remaining distance that Peter needed to travel
= 420 - 195
= 225 km
Time that Peter needed to reach his destination after the two met
= 225 ÷ 65
= 3
3065 = 3
613 h
Answer(s): (a) 75 km/h; (b) 3
613 h