City Z and City A are 480 km apart. At 4.28 p.m., Rael is travelling at a uniform speed left City Z for City A while Owen set off from City A to City Z along the same road at a uniform speed, which was 12 km/h slower than that of Rael. The two met at 8.28 p.m.
- Find the speed of Rael.
- If Owen 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 Rael and Owen to travel from 4.28 p.m. to 8.28 p.m. = 4 h
Average speed of Rael and Owen
= 480 ÷ 4
= 120 km/h
Rael's speed
= (120 + 12) ÷ 2
= 132 ÷ 2
= 66 km/h
(b)
Owen's speed
= 66 - 12
= 54 km/h
Distance that Owen travelled in 4 h
= 4 x 54
= 216 km
Remaining distance that Owen needed to travel
= 480 - 216
= 264 km
Time that Owen needed to reach his destination after the two met
= 264 ÷ 54
= 4
4854 = 4
89 h
Answer(s): (a) 66 km/h; (b) 4
89 h