City B and City C are 480 km apart. At 1.36 p.m., Jenson is travelling at a uniform speed left City B for City C while Valen set off from City C to City B along the same road at a uniform speed, which was 10 km/h slower than that of Jenson. The two met at 5.36 p.m.
- Find the speed of Jenson.
- If Valen 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 Jenson and Valen to travel from 1.36 p.m. to 5.36 p.m. = 4 h
Average speed of Jenson and Valen
= 480 ÷ 4
= 120 km/h
Jenson's speed
= (120 + 10) ÷ 2
= 130 ÷ 2
= 65 km/h
(b)
Valen's speed
= 65 - 10
= 55 km/h
Distance that Valen travelled in 4 h
= 4 x 55
= 220 km
Remaining distance that Valen needed to travel
= 480 - 220
= 260 km
Time that Valen needed to reach his destination after the two met
= 260 ÷ 55
= 4
4055 = 4
811 h
Answer(s): (a) 65 km/h; (b) 4
811 h