City Y and City Z are 396 km apart. At 2.55 p.m., Eric is travelling at a uniform speed left City Y for City Z while Zane set off from City Z to City Y along the same road at a uniform speed, which was 12 km/h slower than that of Eric. The two met at 5.55 p.m.
- Find the speed of Eric.
- If Zane 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 Eric and Zane to travel from 2.55 p.m. to 5.55 p.m. = 3 h
Average speed of Eric and Zane
= 396 ÷ 3
= 132 km/h
Eric's speed
= (132 + 12) ÷ 2
= 144 ÷ 2
= 72 km/h
(b)
Zane's speed
= 72 - 12
= 60 km/h
Distance that Zane travelled in 3 h
= 3 x 60
= 180 km
Remaining distance that Zane needed to travel
= 396 - 180
= 216 km
Time that Zane needed to reach his destination after the two met
= 216 ÷ 60
= 3
3660 = 3
35 h
Answer(s): (a) 72 km/h; (b) 3
35 h