City W and City X are 564 km apart. At 2.47 p.m., Ken is travelling at a uniform speed left City W for City X while Asher set off from City X to City W along the same road at a uniform speed, which was 5 km/h slower than that of Ken. The two met at 6.47 p.m.
- Find the speed of Ken.
- If Asher 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 Ken and Asher to travel from 2.47 p.m. to 6.47 p.m. = 4 h
Average speed of Ken and Asher
= 564 ÷ 4
= 141 km/h
Ken's speed
= (141 + 5) ÷ 2
= 146 ÷ 2
= 73 km/h
(b)
Asher's speed
= 73 - 5
= 68 km/h
Distance that Asher travelled in 4 h
= 4 x 68
= 272 km
Remaining distance that Asher needed to travel
= 564 - 272
= 292 km
Time that Asher needed to reach his destination after the two met
= 292 ÷ 68
= 4
2068 = 4
517 h
Answer(s): (a) 73 km/h; (b) 4
517 h