At 8 a.m., Asher started from City S and travelled towards City T and his speed remained constant throughout. At 9 a.m., Xandra started her journey from City S towards City T at an average speed of 90 km/h. Xandra overtook Asher at 1 p.m. After overtaking, Xandra carried on her journey at the same average speed and reached at City T at 6:40 p.m.

1. Find Asher'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 Xandra had travelled until Xandra overtook Asher
= 4 x 90
= 360 km

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

Asher's average speed
= 360 ÷ 5
= 72 km/h

(b)
From 9 a.m. to 6:40 p.m. = 9 h 40 min

1 h = 60 min
9 h 40 min = 9 ⁴⁰ ₆₀
 h = 9 ²₃ h

Distance between the two cities
= 9 ²₃ x 90
= ²⁹₃ x 90
= 870 km

Answer(s): (a) 72 km/h; (b) 870 km