Vaidev drove from Town Q to Town R which was 672 km away. He started from Town Q at an average speed of 67 km/h. He maintained this speed for 3 h before increasing it by 7 km/h for the rest of the journey to Town R.
- How long did he take to complete the whole journey?
- What was his average speed from Town Q to Town R?
(a)
Distance of 1st part of the journey
= 3 x 67
= 201 km
New speed for rest of the journey
= 67 + 7
= 74 km / h
Remaining distance for rest of the journey
= 672 - 201
= 471 km
Time taken for rest of the journey
= 471 ÷ 74
= 5 h
Total time taken
= 3 + 5
= 8 h
(b)
Average speed of the whole journey
= 672 ÷ 8
= 84 km
Answer(s): (a) 8 h; (b) 84km/h