Vincent left City E for City D at 07 48. Gillian left City E for City C at the same time. At 11 48, they were 720 km apart. Both maintained a constant speed and reached their destination at the same time at 14 12.

1. Find the distance between Cities A and C.
2. If Gillian was ⁵₇ the speed of Vincent, find Vincent's speed.

(a)
Time taken for Vincent and Gillian to travel 07 48 to 11 48 = 4 h
Time taken for Vincent and Gillian to travel 07 48 to 14 12 = 6 h 24 min = 6²⁴₆₀ h = 6²₅ h

Distance travelled by Vincent and Gillian in 1 hour
= 720 ÷ 4
= 180 km

Total distance
= 6²₅ x 180
= 1152 km

(b)
Gillian's distance : Vincent's distance
5 : 7

Gillian's speed : Vincent's speed
5 : 7

12 u = 180 km
1 u = 180 ÷ 12 = 15 km

Vincent's speed
= 7 u
= 7 x 15
= 105 km/h

Answer(s): (a) 1152 km; (b) 105km/h