City E and City F are 468 km apart. At 1.22 p.m., Mark is travelling at a uniform speed left City E for City F while Julian set off from City F to City E along the same road at a uniform speed, which was 6 km/h slower than that of Mark. The two met at 3.22 p.m.
- Find the speed of Mark.
- If Julian 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 Mark and Julian to travel from 1.22 p.m. to 3.22 p.m. = 2 h
Average speed of Mark and Julian
= 468 ÷ 2
= 234 km/h
Mark's speed
= (234 + 6) ÷ 2
= 240 ÷ 2
= 120 km/h
(b)
Julian's speed
= 120 - 6
= 114 km/h
Distance that Julian travelled in 2 h
= 2 x 114
= 228 km
Remaining distance that Julian needed to travel
= 468 - 228
= 240 km
Time that Julian needed to reach his destination after the two met
= 240 ÷ 114
= 2
12114 = 2
219 h
Answer(s): (a) 120 km/h; (b) 2
219 h