Bobby drove from Town L to Town M which was 490 km away. He started from Town L at an average speed of 63 km/h. He maintained this speed for 3 h before increasing it by 6 km/h for the rest of the journey to Town M.
- How long did he take to complete the whole journey?
- What was his average speed from Town L to Town M?
(a)
Distance of 1st part of the journey
= 3 x 63
= 189 km
New speed for rest of the journey
= 63 + 6
= 69 km / h
Remaining distance for rest of the journey
= 490 - 189
= 301 km
Time taken for rest of the journey
= 301 ÷ 69
= 4 h
Total time taken
= 3 + 4
= 7 h
(b)
Average speed of the whole journey
= 490 ÷ 7
= 70 km
Answer(s): (a) 7 h; (b) 70km/h