Barbara left home at 8.40 a.m. and drove towards the city which was 649 km away. For the first 234 km, she was travelling at 78 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 234 km
= 234 ÷ 78
= 3 h
Distance of the remaining journey
= 649 - 234
= 415 km
Speed for remaining journey
= 78 + 5
= 83 km/h
Time taken to travel remaining journey
= 415 ÷ 83
= 5 h
Time taken to travel the whole journey
= 5 + 3
= 8 h
(b)
8 h after 8.40 a.m. = 4.40 p.m.
Answer(s): (a) 8 h; (b) 4.40 p.m.