David left City M for City L at 09 41. Ivory left City M for City C at the same time. At 11 41, they were 330 km apart. Both maintained a constant speed and reached their destination at the same time at 13 33.
- Find the distance between Cities A and C.
- If Ivory was 56 the speed of David, find David's speed.
(a)
Time taken for David and Ivory to travel 09 41 to 11 41 = 2 h
Time taken for David and Ivory to travel 09 41 to 13 33 = 3 h 52 min = 3
5260 h = 3
1315 h
Distance travelled by David and Ivory in 1 hour
= 330 ÷ 2
= 165 km
Total distance
= 3
1315 x 165
= 638 km
(b)
Ivory's distance : David's distance
5 : 6
Ivory's speed : David's speed
5 : 6
11 u = 165 km
1 u = 165 ÷ 11 = 15 km
David's speed
= 6 u
= 6 x 15
= 90 km/h
Answer(s): (a) 638 km; (b) 90km/h