At 7 a.m., Zane started from City Y and travelled towards City Z and his speed remained constant throughout. At 10 a.m., Elyse started her journey from City Y towards City Z at an average speed of 80 km/h. Elyse overtook Zane at 1 p.m. After overtaking, Elyse carried on her journey at the same average speed and reached at City Z at 2:15 p.m.

1. Find Zane'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 Elyse had travelled until Elyse overtook Zane
= 3 x 80
= 240 km

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

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

(b)
From 10 a.m. to 2:15 p.m. = 4 h 15 min

1 h = 60 min
4 h 15 min = 4 ¹⁵ ₆₀
 h = 4 ¹₄ h

Distance between the two cities
= 4 ¹₄ x 80
= ¹⁷₄ x 80
= 340 km

Answer(s): (a) 40 km/h; (b) 340 km