Min left home at 5.20 a.m. and drove towards the mountain which was 796 km away. For the first 320 km, she was travelling at 64 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 mountain?
(a)
Time taken to travel 320 km
= 320 ÷ 64
= 5 h
Distance of the remaining journey
= 796 - 320
= 476 km
Speed for remaining journey
= 64 + 4
= 68 km/h
Time taken to travel remaining journey
= 476 ÷ 68
= 7 h
Time taken to travel the whole journey
= 7 + 5
= 12 h
(b)
12 h after 5.20 a.m. = 5.20 p.m.
Answer(s): (a) 12 h; (b) 5.20 p.m.