Jenson drove from Town W to Town X which was 355 km away. He started from Town W at an average speed of 64 km/h. He maintained this speed for 4 h before increasing it by 5 km/h for the rest of the journey to Town X.
- How long did he take to complete the whole journey?
- What was his average speed from Town W to Town X?
(a)
Distance of 1st part of the journey
= 4 x 64
= 256 km
New speed for rest of the journey
= 64 + 5
= 69 km / h
Remaining distance for rest of the journey
= 355 - 256
= 99 km
Time taken for rest of the journey
= 99 ÷ 69
= 1 h
Total time taken
= 4 + 1
= 5 h
(b)
Average speed of the whole journey
= 355 ÷ 5
= 71 km
Answer(s): (a) 5 h; (b) 71km/h