Hazel left home at 7.40 a.m. and drove towards the airport which was 850 km away. For the first 400 km, she was travelling at 80 km/h. Then she increased her speed by 10 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 400 km
= 400 ÷ 80
= 5 h
Distance of the remaining journey
= 850 - 400
= 450 km
Speed for remaining journey
= 80 + 10
= 90 km/h
Time taken to travel remaining journey
= 450 ÷ 90
= 5 h
Time taken to travel the whole journey
= 5 + 5
= 10 h
(b)
10 h after 7.40 a.m. = 5.40 p.m.
Answer(s): (a) 10 h; (b) 5.40 p.m.