Harry drove from Town M to Town N which was 430 km away. He started from Town M at an average speed of 60 km/h. He maintained this speed for 4 h before increasing it by 6 km/h for the rest of the journey to Town N.
- How long did he take to complete the whole journey?
- What was his average speed from Town M to Town N?
(a)
Distance of 1st part of the journey
= 4 x 60
= 240 km
New speed for rest of the journey
= 60 + 6
= 66 km / h
Remaining distance for rest of the journey
= 430 - 240
= 190 km
Time taken for rest of the journey
= 190 ÷ 66
= 1 h
Total time taken
= 4 + 1
= 5 h
(b)
Average speed of the whole journey
= 430 ÷ 5
= 86 km
Answer(s): (a) 5 h; (b) 86km/h