Rael drove from Town B to Town C which was 445 km away. He started from Town B at an average speed of 73 km/h. He maintained this speed for 2 h before increasing it by 5 km/h for the rest of the journey to Town C.
- How long did he take to complete the whole journey?
- What was his average speed from Town B to Town C?
(a)
Distance of 1st part of the journey
= 2 x 73
= 146 km
New speed for rest of the journey
= 73 + 5
= 78 km / h
Remaining distance for rest of the journey
= 445 - 146
= 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
= 445 ÷ 5
= 89 km
Answer(s): (a) 5 h; (b) 89km/h