Mary left home at 10.30 a.m. and drove towards the mountain which was 935 km away. For the first 270 km, she was travelling at 90 km/h. Then she increased her speed by 5 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 270 km
= 270 ÷ 90
= 3 h
Distance of the remaining journey
= 935 - 270
= 665 km
Speed for remaining journey
= 90 + 5
= 95 km/h
Time taken to travel remaining journey
= 665 ÷ 95
= 7 h
Time taken to travel the whole journey
= 7 + 3
= 10 h
(b)
10 h after 10.30 a.m. = 8.30 p.m.
Answer(s): (a) 10 h; (b) 8.30 p.m.