City K and City L are 512 km apart. At 2.14 p.m., Nick is travelling at a uniform speed left City K for City L while Simon set off from City L to City K along the same road at a uniform speed, which was 8 km/h slower than that of Nick. The two met at 6.14 p.m.

1. Find the speed of Nick.
2. 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 Nick and Simon to travel from 2.14 p.m. to 6.14 p.m. = 4 h

Average speed of Nick and Simon
= 512 ÷ 4
= 128 km/h

Nick's speed
= (128 + 8) ÷ 2
= 136 ÷ 2 
= 68 km/h

(b)
Simon's speed
= 68 - 8
= 60 km/h

Distance that Simon travelled in 4 h
= 4 x 60
= 240 km

Remaining distance that Simon needed to travel
= 512 - 240
= 272 km

Time that Simon needed to reach his destination after the two met
= 272 ÷ 60
= 4³²₆₀
= 4⁸₁₅ h

Answer(s): (a) 68 km/h; (b) 4⁸₁₅ h