City B and City C are 426 km apart. At 5.58 p.m., Tommy is travelling at a uniform speed left City B for City C while Simon set off from City C to City B along the same road at a uniform speed, which was 9 km/h slower than that of Tommy. The two met at 7.58 p.m.
- Find the speed of Tommy.
- 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 Tommy and Simon to travel from 5.58 p.m. to 7.58 p.m. = 2 h
Average speed of Tommy and Simon
= 426 ÷ 2
= 213 km/h
Tommy's speed
= (213 + 9) ÷ 2
= 222 ÷ 2
= 111 km/h
(b)
Simon's speed
= 111 - 9
= 102 km/h
Distance that Simon travelled in 2 h
= 2 x 102
= 204 km
Remaining distance that Simon needed to travel
= 426 - 204
= 222 km
Time that Simon needed to reach his destination after the two met
= 222 ÷ 102
= 2
18102 = 2
317 h
Answer(s): (a) 111 km/h; (b) 2
317 h