Vincent drove from Town X to Town Y which was 720 km away. He started from Town X at an average speed of 67 km/h. He maintained this speed for 4 h before increasing it by 8 km/h for the rest of the journey to Town Y.
- How long did he take to complete the whole journey?
- What was his average speed from Town X to Town Y?
(a)
Distance of 1st part of the journey
= 4 x 67
= 268 km
New speed for rest of the journey
= 67 + 8
= 75 km / h
Remaining distance for rest of the journey
= 720 - 268
= 452 km
Time taken for rest of the journey
= 452 ÷ 75
= 4 h
Total time taken
= 4 + 4
= 8 h
(b)
Average speed of the whole journey
= 720 ÷ 8
= 90 km
Answer(s): (a) 8 h; (b) 90km/h