Asher drove from Town J to Town K which was 600 km away. He started from Town J at an average speed of 65 km/h. He maintained this speed for 4 h before increasing it by 5 km/h for the rest of the journey to Town K.
- How long did he take to complete the whole journey?
- What was his average speed from Town J to Town K?
(a)
Distance of 1st part of the journey
= 4 x 65
= 260 km
New speed for rest of the journey
= 65 + 5
= 70 km / h
Remaining distance for rest of the journey
= 600 - 260
= 340 km
Time taken for rest of the journey
= 340 ÷ 70
= 4 h
Total time taken
= 4 + 4
= 8 h
(b)
Average speed of the whole journey
= 600 ÷ 8
= 75 km
Answer(s): (a) 8 h; (b) 75km/h