Rael drove from Town J to Town K which was 360 km away. He started from Town J at an average speed of 62 km/h. He maintained this speed for 3 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
= 3 x 62
= 186 km
New speed for rest of the journey
= 62 + 5
= 67 km / h
Remaining distance for rest of the journey
= 360 - 186
= 174 km
Time taken for rest of the journey
= 174 ÷ 67
= 1 h
Total time taken
= 3 + 1
= 4 h
(b)
Average speed of the whole journey
= 360 ÷ 4
= 90 km
Answer(s): (a) 4 h; (b) 90km/h