City K and City L is 378 km apart. Mark left City K for City L at 11.00 a.m. travelling at an average speed of 63 km/h. Rael left City K later than Mark and caught up with him at 1.00 p.m. Rael was travelling at a speed of 108 km/h.
- At what time did Rael leave City K?
- How much later did Mark arrive in City L than Rael? 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 Mark covered when Rael caught up with Mark
= 2 x 63
= 126 km
Time that Rael took to travel 126 km
= 126 ÷ 108
= 1
16 h
1 h = 60 min
16 h =
16 x 60 = 10 min
1
16 h = 1 h 10 min
Time that Rael left City K:
1 h 10 min before 1.00 p.m. = 11.50 a.m.
(b)
Remaining distance that they had to cover to reach City L
= 378 - 126
= 252 km
Duration that Rael had to travel before reaching City L
= 252 ÷ 108
= 2
13 h
Duration that Mark had to travel before reaching City L
= 252 ÷ 63
= 4 h
Duration that Mark took to arrive later than Rael in City L
= 4 - 2
13= 1
23 h
Answer(s): (a) 11.50 a.m.; (b) 1
23 h
