City K and City L is 345 km apart. Jeremy left City K for City L at 7.00 a.m. travelling at an average speed of 69 km/h. Owen left City K later than Jeremy and caught up with him at 9.00 a.m. Owen was travelling at a speed of 72 km/h.

1. At what time did Owen leave City K?
2. How much later did Jeremy arrive in City L than Owen? Express your answer in h as a fraction or mixed number.

(a)
From 7.00 a.m. to 9.00 a.m. = 2 h

Distance that Jeremy covered when Owen caught up with Jeremy
= 2 x 69
= 138 km

Time that Owen took to travel 138 km
= 138 ÷ 72
= 1¹¹₁₂ h

1 h = 60 min
¹¹₁₂ h = ¹¹₁₂ x 60 = 55 min
1¹¹₁₂ h = 1 h 55 min

Time that Owen left City K:
1 h 55 min before 9.00 a.m. = 7.05 a.m.

(b)
Remaining distance that they had to cover to reach City L
= 345 - 138
= 207 km

Duration that Owen had to travel before reaching City L
= 207 ÷ 72
= 2⁷₈ h

Duration that Jeremy had to travel before reaching City L
= 207 ÷ 69
= 3 h

Duration that Jeremy took to arrive later than Owen in City L
= 3 - 2⁷₈
= ¹₈ h

Answer(s): (a) 7.05 a.m.; (b) ¹₈ h