Elijah drove from Town C to Town D which was 592 km away. He started from Town C at an average speed of 69 km/h. He maintained this speed for 3 h before increasing it by 8 km/h for the rest of the journey to Town D.
- How long did he take to complete the whole journey?
- What was his average speed from Town C to Town D?
(a)
Distance of 1st part of the journey
= 3 x 69
= 207 km
New speed for rest of the journey
= 69 + 8
= 77 km / h
Remaining distance for rest of the journey
= 592 - 207
= 385 km
Time taken for rest of the journey
= 385 ÷ 77
= 5 h
Total time taken
= 3 + 5
= 8 h
(b)
Average speed of the whole journey
= 592 ÷ 8
= 74 km
Answer(s): (a) 8 h; (b) 74km/h