At 7 a.m., Zane started from City X and travelled towards City Y and his speed remained constant throughout. At 8 a.m., Gabby started her journey from City X towards City Y at an average speed of 84 km/h. Gabby overtook Zane at 1 p.m. After overtaking, Gabby carried on her journey at the same average speed and reached at City Y at 1:40 p.m.

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

(a)
From 8 a.m. to 1 p.m. = 5 h

Distance that Gabby had travelled until Gabby overtook Zane
= 5 x 84
= 420 km

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

Zane's average speed
= 420 ÷ 6
= 70 km/h

(b)
From 8 a.m. to 1:40 p.m. = 5 h 40 min

1 h = 60 min
5 h 40 min = 5 ⁴⁰ ₆₀
 h = 5 ²₃ h

Distance between the two cities
= 5 ²₃ x 84
= ¹⁷₃ x 84
= 476 km

Answer(s): (a) 70 km/h; (b) 476 km