Eric drove from Town U to Town V which was 462 km away. He started from Town U at an average speed of 72 km/h. He maintained this speed for 2 h before increasing it by 7 km/h for the rest of the journey to Town V.
- How long did he take to complete the whole journey?
- What was his average speed from Town U to Town V?
(a)
Distance of 1st part of the journey
= 2 x 72
= 144 km
New speed for rest of the journey
= 72 + 7
= 79 km / h
Remaining distance for rest of the journey
= 462 - 144
= 318 km
Time taken for rest of the journey
= 318 ÷ 79
= 4 h
Total time taken
= 2 + 4
= 6 h
(b)
Average speed of the whole journey
= 462 ÷ 6
= 77 km
Answer(s): (a) 6 h; (b) 77km/h