Tiffany left home at 8.35 a.m. and drove towards the city which was 648 km away. For the first 312 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 312 km
= 312 ÷ 78
= 4 h
Distance of the remaining journey
= 648 - 312
= 336 km
Speed for remaining journey
= 78 + 6
= 84 km/h
Time taken to travel remaining journey
= 336 ÷ 84
= 4 h
Time taken to travel the whole journey
= 4 + 4
= 8 h
(b)
8 h after 8.35 a.m. = 4.35 p.m.
Answer(s): (a) 8 h; (b) 4.35 p.m.