City F and City G are 316 km apart. At 5.43 p.m., Jenson is travelling at a uniform speed left City F for City G while Luis set off from City G to City F along the same road at a uniform speed, which was 6 km/h slower than that of Jenson. The two met at 7.43 p.m.
- Find the speed of Jenson.
- If Luis 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 Luis to travel from 5.43 p.m. to 7.43 p.m. = 2 h
Average speed of Jenson and Luis
= 316 ÷ 2
= 158 km/h
Jenson's speed
= (158 + 6) ÷ 2
= 164 ÷ 2
= 82 km/h
(b)
Luis's speed
= 82 - 6
= 76 km/h
Distance that Luis travelled in 2 h
= 2 x 76
= 152 km
Remaining distance that Luis needed to travel
= 316 - 152
= 164 km
Time that Luis needed to reach his destination after the two met
= 164 ÷ 76
= 2
1276 = 2
319 h
Answer(s): (a) 82 km/h; (b) 2
319 h