City R and City S is 420 km apart. Perry left City R for City S at 11.00 a.m. travelling at an average speed of 60 km/h. Neave left City R later than Perry and caught up with him at 2.00 p.m. Neave was travelling at a speed of 72 km/h.

1. At what time did Neave leave City R?
2. How much later did Perry arrive in City S than Neave? 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 Perry covered when Neave caught up with Perry
= 3 x 60
= 180 km

Time that Neave took to travel 180 km
= 180 ÷ 72
= 2¹₂ h

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

Time that Neave left City R:
2 h 30 min before 2.00 p.m. = 11.30 a.m.

(b)
Remaining distance that they had to cover to reach City S
= 420 - 180
= 240 km

Duration that Neave had to travel before reaching City S
= 240 ÷ 72
= 3¹₃ h

Duration that Perry had to travel before reaching City S
= 240 ÷ 60
= 4 h

Duration that Perry took to arrive later than Neave in City S
= 4 - 3¹₃
= ²₃ h

Answer(s): (a) 11.30 a.m.; (b) ²₃ h