At 7 a.m., Rael started from City T and travelled towards City U and his speed remained constant throughout. At 10 a.m., Gwen started her journey from City T towards City U at an average speed of 80 km/h. Gwen overtook Rael at 1 p.m. After overtaking, Gwen carried on her journey at the same average speed and reached at City U at 4:45 p.m.

1. Find Rael's average speed in km/h.
2. What is the distance between the two cities?

(a)
From 10 a.m. to 1 p.m. = 3 h

Distance that Gwen had travelled until Gwen overtook Rael
= 3 x 80
= 240 km

From 7 a.m. to 1 p.m. = 6 h

Rael's average speed
= 240 ÷ 6
= 40 km/h

(b)
From 10 a.m. to 4:45 p.m. = 6 h 45 min

1 h = 60 min
6 h 45 min = 6 ⁴⁵ ₆₀
 h = 6 ³₄ h

Distance between the two cities
= 6 ³₄ x 80
= ²⁷₄ x 80
= 540 km

Answer(s): (a) 40 km/h; (b) 540 km