Sarah left home at 5.30 a.m. and drove towards the mountain which was 1140 km away. For the first 540 km, she was travelling at 90 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 mountain?
(a)
Time taken to travel 540 km
= 540 ÷ 90
= 6 h
Distance of the remaining journey
= 1140 - 540
= 600 km
Speed for remaining journey
= 90 + 10
= 100 km/h
Time taken to travel remaining journey
= 600 ÷ 100
= 6 h
Time taken to travel the whole journey
= 6 + 6
= 12 h
(b)
12 h after 5.30 a.m. = 5.30 p.m.
Answer(s): (a) 12 h; (b) 5.30 p.m.