Barbara left home at 5.50 a.m. and drove towards the mountain which was 678 km away. For the first 216 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 mountain?
(a)
Time taken to travel 216 km
= 216 ÷ 72
= 3 h
Distance of the remaining journey
= 678 - 216
= 462 km
Speed for remaining journey
= 72 + 5
= 77 km/h
Time taken to travel remaining journey
= 462 ÷ 77
= 6 h
Time taken to travel the whole journey
= 6 + 3
= 9 h
(b)
9 h after 5.50 a.m. = 2.50 p.m.
Answer(s): (a) 9 h; (b) 2.50 p.m.