City G and City H are 480 km apart. At 5.44 p.m., Jenson is travelling at a uniform speed left City G for City H while Lee set off from City H to City G along the same road at a uniform speed, which was 6 km/h slower than that of Jenson. The two met at 9.44 p.m.

1. Find the speed of Jenson.
2. If Lee 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 Jenson and Lee to travel from 5.44 p.m. to 9.44 p.m. = 4 h

Average speed of Jenson and Lee
= 480 ÷ 4
= 120 km/h

Jenson's speed
= (120 + 6) ÷ 2
= 126 ÷ 2 
= 63 km/h

(b)
Lee's speed
= 63 - 6
= 57 km/h

Distance that Lee travelled in 4 h
= 4 x 57
= 228 km

Remaining distance that Lee needed to travel
= 480 - 228
= 252 km

Time that Lee needed to reach his destination after the two met
= 252 ÷ 57
= 4²⁴₅₇
= 4⁸₁₉ h

Answer(s): (a) 63 km/h; (b) 4⁸₁₉ h