At 9 a.m., Asher started from City G and travelled towards City H and his speed remained constant throughout. At 10 a.m., Erika started her journey from City G towards City H at an average speed of 68 km/h. Erika overtook Asher at 1 p.m. After overtaking, Erika carried on her journey at the same average speed and reached at City H at 2:30 p.m.

1. Find Asher'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 Erika had travelled until Erika overtook Asher
= 3 x 68
= 204 km

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

Asher's average speed
= 204 ÷ 4
= 51 km/h

(b)
From 10 a.m. to 2:30 p.m. = 4 h 30 min

1 h = 60 min
4 h 30 min = 4 ³⁰ ₆₀
 h = 4 ¹₂ h

Distance between the two cities
= 4 ¹₂ x 68
= ⁹₂ x 68
= 306 km

Answer(s): (a) 51 km/h; (b) 306 km