Julie left home at 10.30 a.m. and drove towards the airport which was 685 km away. For the first 320 km, she was travelling at 64 km/h. Then she increased her speed by 9 km/h and completed the remaining journey.
- How long did she take for her whole journey?
- At what time did she reach the airport?
(a)
Time taken to travel 320 km
= 320 ÷ 64
= 5 h
Distance of the remaining journey
= 685 - 320
= 365 km
Speed for remaining journey
= 64 + 9
= 73 km/h
Time taken to travel remaining journey
= 365 ÷ 73
= 5 h
Time taken to travel the whole journey
= 5 + 5
= 10 h
(b)
10 h after 10.30 a.m. = 8.30 p.m.
Answer(s): (a) 10 h; (b) 8.30 p.m.