Oscar drove from Town J to Town K which was 350 km away. He started from Town J at an average speed of 62 km/h. He maintained this speed for 4 h before increasing it by 9 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 62
= 248 km
New speed for rest of the journey
= 62 + 9
= 71 km / h
Remaining distance for rest of the journey
= 350 - 248
= 102 km
Time taken for rest of the journey
= 102 ÷ 71
= 1 h
Total time taken
= 4 + 1
= 5 h
(b)
Average speed of the whole journey
= 350 ÷ 5
= 70 km
Answer(s): (a) 5 h; (b) 70km/h