Winnie left home at 8.20 a.m. and drove towards the airport which was 745 km away. For the first 405 km, she was travelling at 81 km/h. Then she increased her speed by 4 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 405 km
= 405 ÷ 81
= 5 h
Distance of the remaining journey
= 745 - 405
= 340 km
Speed for remaining journey
= 81 + 4
= 85 km/h
Time taken to travel remaining journey
= 340 ÷ 85
= 4 h
Time taken to travel the whole journey
= 4 + 5
= 9 h
(b)
9 h after 8.20 a.m. = 5.20 p.m.
Answer(s): (a) 9 h; (b) 5.20 p.m.