Glen drove from Town V to Town W which was 324 km away. He started from Town V at an average speed of 68 km/h. He maintained this speed for 3 h before increasing it by 4 km/h for the rest of the journey to Town W.
- How long did he take to complete the whole journey?
- What was his average speed from Town V to Town W?
(a)
Distance of 1st part of the journey
= 3 x 68
= 204 km
New speed for rest of the journey
= 68 + 4
= 72 km / h
Remaining distance for rest of the journey
= 324 - 204
= 120 km
Time taken for rest of the journey
= 120 ÷ 72
= 1 h
Total time taken
= 3 + 1
= 4 h
(b)
Average speed of the whole journey
= 324 ÷ 4
= 81 km
Answer(s): (a) 4 h; (b) 81km/h