City L and City M is 480 km apart. Julian left City L for City M at 10.00 a.m. travelling at an average speed of 80 km/h. Tommy left City L later than Julian and caught up with him at 1.00 p.m. Tommy was travelling at a speed of 96 km/h.

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

(a)
From 10.00 a.m. to 1.00 p.m. = 3 h

Distance that Julian covered when Tommy caught up with Julian
= 3 x 80
= 240 km

Time that Tommy took to travel 240 km
= 240 ÷ 96
= 2¹₂ h

1 h = 60 min
¹₂ h = ¹₂ x 60 = 30 min
2¹₂ h = 2 h 30 min

Time that Tommy left City L:
2 h 30 min before 1.00 p.m. = 10.30 a.m.

(b)
Remaining distance that they had to cover to reach City M
= 480 - 240
= 240 km

Duration that Tommy had to travel before reaching City M
= 240 ÷ 96
= 2¹₂ h

Duration that Julian had to travel before reaching City M
= 240 ÷ 80
= 3 h

Duration that Julian took to arrive later than Tommy in City M
= 3 - 2¹₂
= ¹₂ h

Answer(s): (a) 10.30 a.m.; (b) ¹₂ h