Billy left City L for City K at 08 50. Vanessa left City L for City C at the same time. At 12 50, they were 720 km apart. Both maintained a constant speed and reached their destination at the same time at 14 15.

1. Find the distance between Cities A and C.
2. If Vanessa was ⁷₈ the speed of Billy, find Billy's speed.

(a)
Time taken for Billy and Vanessa to travel 08 50 to 12 50 = 4 h
Time taken for Billy and Vanessa to travel 08 50 to 14 15 = 5 h 25 min = 5²⁵₆₀ h = 5⁵₁₂ h

Distance travelled by Billy and Vanessa in 1 hour
= 720 ÷ 4
= 180 km

Total distance
= 5⁵₁₂ x 180
= 975 km

(b)
Vanessa's distance : Billy's distance
7 : 8

Vanessa's speed : Billy's speed
7 : 8

15 u = 180 km
1 u = 180 ÷ 15 = 12 km

Billy's speed
= 8 u
= 8 x 12
= 96 km/h

Answer(s): (a) 975 km; (b) 96km/h