Jenson drove from Town G to Town H which was 474 km away. He started from Town G at an average speed of 71 km/h. He maintained this speed for 3 h before increasing it by 10 km/h for the rest of the journey to Town H.
- How long did he take to complete the whole journey?
- What was his average speed from Town G to Town H?
(a)
Distance of 1st part of the journey
= 3 x 71
= 213 km
New speed for rest of the journey
= 71 + 10
= 81 km / h
Remaining distance for rest of the journey
= 474 - 213
= 261 km
Time taken for rest of the journey
= 261 ÷ 81
= 3 h
Total time taken
= 3 + 3
= 6 h
(b)
Average speed of the whole journey
= 474 ÷ 6
= 79 km
Answer(s): (a) 6 h; (b) 79km/h