Howard drove from Town X to Town Y which was 553 km away. He started from Town X at an average speed of 71 km/h. He maintained this speed for 3 h before increasing it by 8 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
= 3 x 71
= 213 km
New speed for rest of the journey
= 71 + 8
= 79 km / h
Remaining distance for rest of the journey
= 553 - 213
= 340 km
Time taken for rest of the journey
= 340 ÷ 79
= 4 h
Total time taken
= 3 + 4
= 7 h
(b)
Average speed of the whole journey
= 553 ÷ 7
= 79 km
Answer(s): (a) 7 h; (b) 79km/h