City G and City H is 544 km apart. Cole left City G for City H at 10.00 a.m. travelling at an average speed of 68 km/h. Lee left City G later than Cole and caught up with him at 2.00 p.m. Lee was travelling at a speed of 102 km/h.

1. At what time did Lee leave City G?
2. How much later did Cole arrive in City H than Lee? Express your answer in h as a fraction or mixed number.

(a)
From 10.00 a.m. to 2.00 p.m. = 4 h

Distance that Cole covered when Lee caught up with Cole
= 4 x 68
= 272 km

Time that Lee took to travel 272 km
= 272 ÷ 102
= 2²₃ h

1 h = 60 min
²₃ h = ²₃ x 60 = 40 min
2²₃ h = 2 h 40 min

Time that Lee left City G:
2 h 40 min before 2.00 p.m. = 11.20 a.m.

(b)
Remaining distance that they had to cover to reach City H
= 544 - 272
= 272 km

Duration that Lee had to travel before reaching City H
= 272 ÷ 102
= 2²₃ h

Duration that Cole had to travel before reaching City H
= 272 ÷ 68
= 4 h

Duration that Cole took to arrive later than Lee in City H
= 4 - 2²₃
= 1¹₃ h

Answer(s): (a) 11.20 a.m.; (b) 1¹₃ h