City V and City W is 560 km apart. Henry left City V for City W at 7.00 a.m. travelling at an average speed of 70 km/h. Gabriel left City V later than Henry and caught up with him at 10.00 a.m. Gabriel was travelling at a speed of 90 km/h.

1. At what time did Gabriel leave City V?
2. How much later did Henry arrive in City W than Gabriel? Express your answer in h as a fraction or mixed number.

(a)
From 7.00 a.m. to 10.00 a.m. = 3 h

Distance that Henry covered when Gabriel caught up with Henry
= 3 x 70
= 210 km

Time that Gabriel took to travel 210 km
= 210 ÷ 90
= 2¹₃ h

1 h = 60 min
¹₃ h = ¹₃ x 60 = 20 min
2¹₃ h = 2 h 20 min

Time that Gabriel left City V:
2 h 20 min before 10.00 a.m. = 7.40 a.m.

(b)
Remaining distance that they had to cover to reach City W
= 560 - 210
= 350 km

Duration that Gabriel had to travel before reaching City W
= 350 ÷ 90
= 3⁸₉ h

Duration that Henry had to travel before reaching City W
= 350 ÷ 70
= 5 h

Duration that Henry took to arrive later than Gabriel in City W
= 5 - 3⁸₉
= 1¹₉ h

Answer(s): (a) 7.40 a.m.; (b) 1¹₉ h