Diana left home at 8.45 a.m. and drove towards the city which was 971 km away. For the first 432 km, she was travelling at 72 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 city?
(a)
Time taken to travel 432 km
= 432 ÷ 72
= 6 h
Distance of the remaining journey
= 971 - 432
= 539 km
Speed for remaining journey
= 72 + 5
= 77 km/h
Time taken to travel remaining journey
= 539 ÷ 77
= 7 h
Time taken to travel the whole journey
= 7 + 6
= 13 h
(b)
13 h after 8.45 a.m. = 9.45 p.m.
Answer(s): (a) 13 h; (b) 9.45 p.m.