City U and City V are 310 km apart. At 5.26 p.m., Elijah is travelling at a uniform speed left City U for City V while Simon set off from City V to City U along the same road at a uniform speed, which was 5 km/h slower than that of Elijah. The two met at 7.26 p.m.
- Find the speed of Elijah.
- If Simon 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 Elijah and Simon to travel from 5.26 p.m. to 7.26 p.m. = 2 h
Average speed of Elijah and Simon
= 310 ÷ 2
= 155 km/h
Elijah's speed
= (155 + 5) ÷ 2
= 160 ÷ 2
= 80 km/h
(b)
Simon's speed
= 80 - 5
= 75 km/h
Distance that Simon travelled in 2 h
= 2 x 75
= 150 km
Remaining distance that Simon needed to travel
= 310 - 150
= 160 km
Time that Simon needed to reach his destination after the two met
= 160 ÷ 75
= 2
1075 = 2
215 h
Answer(s): (a) 80 km/h; (b) 2
215 h