Tommy drove from Town X to Town Y which was 380 km away. He started from Town X at an average speed of 74 km/h. He maintained this speed for 3 h before increasing it by 7 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 74
= 222 km
New speed for rest of the journey
= 74 + 7
= 81 km / h
Remaining distance for rest of the journey
= 380 - 222
= 158 km
Time taken for rest of the journey
= 158 ÷ 81
= 2 h
Total time taken
= 3 + 2
= 5 h
(b)
Average speed of the whole journey
= 380 ÷ 5
= 76 km
Answer(s): (a) 5 h; (b) 76km/h