City E and City F are 420 km apart. At 2.42 p.m., Carl is travelling at a uniform speed left City E for City F while Asher set off from City F to City E along the same road at a uniform speed, which was 8 km/h slower than that of Carl. The two met at 5.42 p.m.
- Find the speed of Carl.
- 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 Carl and Asher to travel from 2.42 p.m. to 5.42 p.m. = 3 h
Average speed of Carl and Asher
= 420 ÷ 3
= 140 km/h
Carl's speed
= (140 + 8) ÷ 2
= 148 ÷ 2
= 74 km/h
(b)
Asher's speed
= 74 - 8
= 66 km/h
Distance that Asher travelled in 3 h
= 3 x 66
= 198 km
Remaining distance that Asher needed to travel
= 420 - 198
= 222 km
Time that Asher needed to reach his destination after the two met
= 222 ÷ 66
= 3
2466 = 3
411 h
Answer(s): (a) 74 km/h; (b) 3
411 h