Abi left home at 7.50 a.m. and drove towards the city which was 810 km away. For the first 390 km, she was travelling at 78 km/h. Then she increased her speed by 6 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 390 km
= 390 ÷ 78
= 5 h
Distance of the remaining journey
= 810 - 390
= 420 km
Speed for remaining journey
= 78 + 6
= 84 km/h
Time taken to travel remaining journey
= 420 ÷ 84
= 5 h
Time taken to travel the whole journey
= 5 + 5
= 10 h
(b)
10 h after 7.50 a.m. = 5.50 p.m.
Answer(s): (a) 10 h; (b) 5.50 p.m.