Perry started driving from City Q towards City R at 13 40 at an average speed of 60 km/h. Vincent began driving from City Q towards City R at 15 20 at an average speed of 100 km/h.
- At what time did Vincent pass Perry on the road?
- 114 hours after passing Perry, Vincent reached City R. At what time did Perry reach City R?
(a)
From 13 40 to 15 20 = 1 h 40 min
Time that Perry travelled before Vincent started driving = 1 h 40 min
1 h = 60 min
1 h 40 min = 1
4060 h = 1
23 h
Distance that Perry travelled before Vincent started driving
= 1
23 x 60
=
53 x 60
= 100 km
Difference between Vincent's and Perry's speed
= 100 - 60
= 40 km/h
Time that Vincent took to catch up with Perry
= 100 ÷ 40
= 2.5 h
= 2 h 30 min
2 h 30 min after 15 20 = 17 50
Time that Vincent passed Perry on the road = 17 50
(b)
1
14 h = 1 h 15 min
Total time that Vincent travelled
= 1 h 15 min + 2 h 30 min
= 3 h 45 min
3 h 45 min = 3
4560h = 3
34h
Distance between City Q and City R
= 3
34 x 100
= 375 km
Time that Perry travelled from City Q to City R
= 375 ÷ 60
= 6.25 h
= 6 h 15 min
6 h 15 min after 13 40 = 19 55
Time that Perry reached City R = 19 55
Answer: (a) 17 50; (b) 19 55