City J and City K are 456 km apart. At 1.32 p.m., Jenson is travelling at a uniform speed left City J for City K while Warren set off from City K to City J along the same road at a uniform speed, which was 8 km/h slower than that of Jenson. The two met at 4.32 p.m.
- Find the speed of Jenson.
- If Warren 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 Warren to travel from 1.32 p.m. to 4.32 p.m. = 3 h
Average speed of Jenson and Warren
= 456 ÷ 3
= 152 km/h
Jenson's speed
= (152 + 8) ÷ 2
= 160 ÷ 2
= 80 km/h
(b)
Warren's speed
= 80 - 8
= 72 km/h
Distance that Warren travelled in 3 h
= 3 x 72
= 216 km
Remaining distance that Warren needed to travel
= 456 - 216
= 240 km
Time that Warren needed to reach his destination after the two met
= 240 ÷ 72
= 3
2472 = 3
13 h
Answer(s): (a) 80 km/h; (b) 3
13 h