City Y and City Z are 480 km apart. At 6.41 p.m., George is travelling at a uniform speed left City Y for City Z while Carl set off from City Z to City Y along the same road at a uniform speed, which was 8 km/h slower than that of George. The two met at 9.41 p.m.
- Find the speed of George.
- If Carl 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 George and Carl to travel from 6.41 p.m. to 9.41 p.m. = 3 h
Average speed of George and Carl
= 480 ÷ 3
= 160 km/h
George's speed
= (160 + 8) ÷ 2
= 168 ÷ 2
= 84 km/h
(b)
Carl's speed
= 84 - 8
= 76 km/h
Distance that Carl travelled in 3 h
= 3 x 76
= 228 km
Remaining distance that Carl needed to travel
= 480 - 228
= 252 km
Time that Carl needed to reach his destination after the two met
= 252 ÷ 76
= 3
2476 = 3
619 h
Answer(s): (a) 84 km/h; (b) 3
619 h