City H and City J are 588 km apart. At 4.52 p.m., Billy is travelling at a uniform speed left City H for City J while Asher set off from City J to City H along the same road at a uniform speed, which was 7 km/h slower than that of Billy. The two met at 8.52 p.m.
- Find the speed of Billy.
- 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 Billy and Asher to travel from 4.52 p.m. to 8.52 p.m. = 4 h
Average speed of Billy and Asher
= 588 ÷ 4
= 147 km/h
Billy's speed
= (147 + 7) ÷ 2
= 154 ÷ 2
= 77 km/h
(b)
Asher's speed
= 77 - 7
= 70 km/h
Distance that Asher travelled in 4 h
= 4 x 70
= 280 km
Remaining distance that Asher needed to travel
= 588 - 280
= 308 km
Time that Asher needed to reach his destination after the two met
= 308 ÷ 70
= 4
2870 = 4
25 h
Answer(s): (a) 77 km/h; (b) 4
25 h