City D and City E are 316 km apart. At 4.47 p.m., Seth is travelling at a uniform speed left City D for City E while Nick set off from City E to City D along the same road at a uniform speed, which was 6 km/h slower than that of Seth. The two met at 6.47 p.m.
- Find the speed of Seth.
- If Nick 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 Seth and Nick to travel from 4.47 p.m. to 6.47 p.m. = 2 h
Average speed of Seth and Nick
= 316 ÷ 2
= 158 km/h
Seth's speed
= (158 + 6) ÷ 2
= 164 ÷ 2
= 82 km/h
(b)
Nick's speed
= 82 - 6
= 76 km/h
Distance that Nick travelled in 2 h
= 2 x 76
= 152 km
Remaining distance that Nick needed to travel
= 316 - 152
= 164 km
Time that Nick 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