At 7 a.m., Neave started from City G and travelled towards City H and his speed remained constant throughout. At 9 a.m., Xuan started her journey from City G towards City H at an average speed of 84 km/h. Xuan overtook Neave at 1 p.m. After overtaking, Xuan carried on her journey at the same average speed and reached at City H at 5:40 p.m.

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

(a)
From 9 a.m. to 1 p.m. = 4 h

Distance that Xuan had travelled until Xuan overtook Neave
= 4 x 84
= 336 km

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

Neave's average speed
= 336 ÷ 6
= 56 km/h

(b)
From 9 a.m. to 5:40 p.m. = 8 h 40 min

1 h = 60 min
8 h 40 min = 8 ⁴⁰ ₆₀
 h = 8 ²₃ h

Distance between the two cities
= 8 ²₃ x 84
= ²⁶₃ x 84
= 728 km

Answer(s): (a) 56 km/h; (b) 728 km