Justin drove from Town X to Town Y which was 504 km away. He started from Town X at an average speed of 62 km/h. He maintained this speed for 2 h before increasing it by 5 km/h for the rest of the journey to Town Y.
- How long did he take to complete the whole journey?
- What was his average speed from Town X to Town Y?
(a)
Distance of 1st part of the journey
= 2 x 62
= 124 km
New speed for rest of the journey
= 62 + 5
= 67 km / h
Remaining distance for rest of the journey
= 504 - 124
= 380 km
Time taken for rest of the journey
= 380 ÷ 67
= 4 h
Total time taken
= 2 + 4
= 6 h
(b)
Average speed of the whole journey
= 504 ÷ 6
= 84 km
Answer(s): (a) 6 h; (b) 84km/h