City Y and City Z are 556 km apart. At 2.12 p.m., Ken is travelling at a uniform speed left City Y for City Z while George set off from City Z to City Y along the same road at a uniform speed, which was 11 km/h slower than that of Ken. The two met at 6.12 p.m.
- Find the speed of Ken.
- If George 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 George to travel from 2.12 p.m. to 6.12 p.m. = 4 h
Average speed of Ken and George
= 556 ÷ 4
= 139 km/h
Ken's speed
= (139 + 11) ÷ 2
= 150 ÷ 2
= 75 km/h
(b)
George's speed
= 75 - 11
= 64 km/h
Distance that George travelled in 4 h
= 4 x 64
= 256 km
Remaining distance that George needed to travel
= 556 - 256
= 300 km
Time that George needed to reach his destination after the two met
= 300 ÷ 64
= 4
4464 = 4
1116 h
Answer(s): (a) 75 km/h; (b) 4
1116 h