City M and City N is 462 km apart. Jack left City M for City N at 10.00 a.m. travelling at an average speed of 77 km/h. Simon left City M later than Jack and caught up with him at 12.00 p.m. Simon was travelling at a speed of 84 km/h.
- At what time did Simon leave City M?
- How much later did Jack arrive in City N than Simon? Express your answer in h as a fraction or mixed number.
(a)
From 10.00 a.m. to 12.00 p.m. = 2 h
Distance that Jack covered when Simon caught up with Jack
= 2 x 77
= 154 km
Time that Simon took to travel 154 km
= 154 ÷ 84
= 1
56 h
1 h = 60 min
56 h =
56 x 60 = 50 min
1
56 h = 1 h 50 min
Time that Simon left City M:
1 h 50 min before 12.00 p.m. = 10.10 a.m.
(b)
Remaining distance that they had to cover to reach City N
= 462 - 154
= 308 km
Duration that Simon had to travel before reaching City N
= 308 ÷ 84
= 3
23 h
Duration that Jack had to travel before reaching City N
= 308 ÷ 77
= 4 h
Duration that Jack took to arrive later than Simon in City N
= 4 - 3
23=
13 h
Answer(s): (a) 10.10 a.m.; (b)
13 h