Erika left home at 8.45 a.m. and drove towards the mountain which was 540 km away. For the first 216 km, she was travelling at 72 km/h. Then she increased her speed by 9 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
= 540 - 216
= 324 km
Speed for remaining journey
= 72 + 9
= 81 km/h
Time taken to travel remaining journey
= 324 ÷ 81
= 4 h
Time taken to travel the whole journey
= 4 + 3
= 7 h
(b)
7 h after 8.45 a.m. = 3.45 p.m.
Answer(s): (a) 7 h; (b) 3.45 p.m.