Bryan drove from Town N to Town P which was 435 km away. He started from Town N at an average speed of 68 km/h. He maintained this speed for 2 h before increasing it by 10 km/h for the rest of the journey to Town P.
- How long did he take to complete the whole journey?
- What was his average speed from Town N to Town P?
(a)
Distance of 1st part of the journey
= 2 x 68
= 136 km
New speed for rest of the journey
= 68 + 10
= 78 km / h
Remaining distance for rest of the journey
= 435 - 136
= 299 km
Time taken for rest of the journey
= 299 ÷ 78
= 3 h
Total time taken
= 2 + 3
= 5 h
(b)
Average speed of the whole journey
= 435 ÷ 5
= 87 km
Answer(s): (a) 5 h; (b) 87km/h