Glen drove from Town Z to Town A which was 602 km away. He started from Town Z at an average speed of 70 km/h. He maintained this speed for 4 h before increasing it by 4 km/h for the rest of the journey to Town A.
- How long did he take to complete the whole journey?
- What was his average speed from Town Z to Town A?
(a)
Distance of 1st part of the journey
= 4 x 70
= 280 km
New speed for rest of the journey
= 70 + 4
= 74 km / h
Remaining distance for rest of the journey
= 602 - 280
= 322 km
Time taken for rest of the journey
= 322 ÷ 74
= 3 h
Total time taken
= 4 + 3
= 7 h
(b)
Average speed of the whole journey
= 602 ÷ 7
= 86 km
Answer(s): (a) 7 h; (b) 86km/h