City Z and City A is 370 km apart. Vaidev left City Z for City A at 11.00 a.m. travelling at an average speed of 74 km/h. Zeph left City Z later than Vaidev and caught up with him at 1.00 p.m. Zeph was travelling at a speed of 111 km/h.

1. At what time did Zeph leave City Z?
2. How much later did Vaidev arrive in City A than Zeph? Express your answer in h as a fraction or mixed number.

(a)
From 11.00 a.m. to 1.00 p.m. = 2 h

Distance that Vaidev covered when Zeph caught up with Vaidev
= 2 x 74
= 148 km

Time that Zeph took to travel 148 km
= 148 ÷ 111
= 1¹₃ h

1 h = 60 min
¹₃ h = ¹₃ x 60 = 20 min
1¹₃ h = 1 h 20 min

Time that Zeph left City Z:
1 h 20 min before 1.00 p.m. = 11.40 a.m.

(b)
Remaining distance that they had to cover to reach City A
= 370 - 148
= 222 km

Duration that Zeph had to travel before reaching City A
= 222 ÷ 111
= 2 h

Duration that Vaidev had to travel before reaching City A
= 222 ÷ 74
= 3 h

Duration that Vaidev took to arrive later than Zeph in City A
= 3 - 2
= 1 h

Answer(s): (a) 11.40 a.m.; (b) 1 h