City U and City V are 363 km apart. At 5.51 p.m., Valen is travelling at a uniform speed left City U for City V while Albert set off from City V to City U along the same road at a uniform speed, which was 11 km/h slower than that of Valen. The two met at 8.51 p.m.
- Find the speed of Valen.
- If Albert 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 Valen and Albert to travel from 5.51 p.m. to 8.51 p.m. = 3 h
Average speed of Valen and Albert
= 363 ÷ 3
= 121 km/h
Valen's speed
= (121 + 11) ÷ 2
= 132 ÷ 2
= 66 km/h
(b)
Albert's speed
= 66 - 11
= 55 km/h
Distance that Albert travelled in 3 h
= 3 x 55
= 165 km
Remaining distance that Albert needed to travel
= 363 - 165
= 198 km
Time that Albert needed to reach his destination after the two met
= 198 ÷ 55
= 3
3355 = 3
35 h
Answer(s): (a) 66 km/h; (b) 3
35 h