At 8 a.m., Reggie started from City X and travelled towards City Y and his speed remained constant throughout. At 10 a.m., Lynn started her journey from City X towards City Y at an average speed of 90 km/h. Lynn overtook Reggie at 1 p.m. After overtaking, Lynn carried on her journey at the same average speed and reached at City Y at 4:30 p.m.

1. Find Reggie'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 Lynn had travelled until Lynn overtook Reggie
= 3 x 90
= 270 km

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

Reggie's average speed
= 270 ÷ 5
= 54 km/h

(b)
From 10 a.m. to 4:30 p.m. = 6 h 30 min

1 h = 60 min
6 h 30 min = 6 ³⁰ ₆₀
 h = 6 ¹₂ h

Distance between the two cities
= 6 ¹₂ x 90
= ¹³₂ x 90
= 585 km

Answer(s): (a) 54 km/h; (b) 585 km