Luis left City Y for City X at 07 15. Mary left City Y for City C at the same time. At 10 15, they were 495 km apart. Both maintained a constant speed and reached their destination at the same time at 14 11.
- Find the distance between Cities A and C.
- If Mary was 47 the speed of Luis, find Luis's speed.
(a)
Time taken for Luis and Mary to travel 07 15 to 10 15 = 3 h
Time taken for Luis and Mary to travel 07 15 to 14 11 = 6 h 56 min = 6
5660 h = 6
1415 h
Distance travelled by Luis and Mary in 1 hour
= 495 ÷ 3
= 165 km
Total distance
= 6
1415 x 165
= 1144 km
(b)
Mary's distance : Luis's distance
4 : 7
Mary's speed : Luis's speed
4 : 7
11 u = 165 km
1 u = 165 ÷ 11 = 15 km
Luis's speed
= 7 u
= 7 x 15
= 105 km/h
Answer(s): (a) 1144 km; (b) 105km/h