Carl left City Q for City P at 06 47. Mary left City Q for City C at the same time. At 10 47, they were 720 km apart. Both maintained a constant speed and reached their destination at the same time at 13 35.
- Find the distance between Cities A and C.
- If Mary was 78 the speed of Carl, find Carl's speed.
(a)
Time taken for Carl and Mary to travel 06 47 to 10 47 = 4 h
Time taken for Carl and Mary to travel 06 47 to 13 35 = 6 h 48 min = 6
4860 h = 6
45 h
Distance travelled by Carl and Mary in 1 hour
= 720 ÷ 4
= 180 km
Total distance
= 6
45 x 180
= 1224 km
(b)
Mary's distance : Carl's distance
7 : 8
Mary's speed : Carl's speed
7 : 8
15 u = 180 km
1 u = 180 ÷ 15 = 12 km
Carl's speed
= 8 u
= 8 x 12
= 96 km/h
Answer(s): (a) 1224 km; (b) 96km/h