Ethan drove from Town W to Town X which was 430 km away. He started from Town W at an average speed of 69 km/h. He maintained this speed for 3 h before increasing it by 9 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
= 3 x 69
= 207 km
New speed for rest of the journey
= 69 + 9
= 78 km / h
Remaining distance for rest of the journey
= 430 - 207
= 223 km
Time taken for rest of the journey
= 223 ÷ 78
= 2 h
Total time taken
= 3 + 2
= 5 h
(b)
Average speed of the whole journey
= 430 ÷ 5
= 86 km
Answer(s): (a) 5 h; (b) 86km/h