Nora left home at 7.40 a.m. and drove towards the airport which was 743 km away. For the first 308 km, she was travelling at 77 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 308 km
= 308 ÷ 77
= 4 h
Distance of the remaining journey
= 743 - 308
= 435 km
Speed for remaining journey
= 77 + 10
= 87 km/h
Time taken to travel remaining journey
= 435 ÷ 87
= 5 h
Time taken to travel the whole journey
= 5 + 4
= 9 h
(b)
9 h after 7.40 a.m. = 4.40 p.m.
Answer(s): (a) 9 h; (b) 4.40 p.m.