City K and City L is 560 km apart. Warren left City K for City L at 11.00 a.m. travelling at an average speed of 80 km/h. Jeremy left City K later than Warren and caught up with him at 2.00 p.m. Jeremy was travelling at a speed of 90 km/h.

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

(a)
From 11.00 a.m. to 2.00 p.m. = 3 h

Distance that Warren covered when Jeremy caught up with Warren
= 3 x 80
= 240 km

Time that Jeremy took to travel 240 km
= 240 ÷ 90
= 2²₃ h

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

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

(b)
Remaining distance that they had to cover to reach City L
= 560 - 240
= 320 km

Duration that Jeremy had to travel before reaching City L
= 320 ÷ 90
= 3⁵₉ h

Duration that Warren had to travel before reaching City L
= 320 ÷ 80
= 4 h

Duration that Warren took to arrive later than Jeremy in City L
= 4 - 3⁵₉
= ⁴₉ h

Answer(s): (a) 11.20 a.m.; (b) ⁴₉ h