Vincent drove from Town S to Town T which was 602 km away. He started from Town S at an average speed of 77 km/h. He maintained this speed for 3 h before increasing it by 9 km/h for the rest of the journey to Town T.
- How long did he take to complete the whole journey?
- What was his average speed from Town S to Town T?
(a)
Distance of 1st part of the journey
= 3 x 77
= 231 km
New speed for rest of the journey
= 77 + 9
= 86 km / h
Remaining distance for rest of the journey
= 602 - 231
= 371 km
Time taken for rest of the journey
= 371 ÷ 86
= 4 h
Total time taken
= 3 + 4
= 7 h
(b)
Average speed of the whole journey
= 602 ÷ 7
= 86 km
Answer(s): (a) 7 h; (b) 86km/h