At 7 a.m., Seth started from City P and travelled towards City Q and his speed remained constant throughout. At 8 a.m., Xylia started her journey from City P towards City Q at an average speed of 72 km/h. Xylia overtook Seth at 1 p.m. After overtaking, Xylia carried on her journey at the same average speed and reached at City Q at 1:45 p.m.

1. Find Seth'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 Xylia had travelled until Xylia overtook Seth
= 5 x 72
= 360 km

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

Seth's average speed
= 360 ÷ 6
= 60 km/h

(b)
From 8 a.m. to 1:45 p.m. = 5 h 45 min

1 h = 60 min
5 h 45 min = 5 ⁴⁵ ₆₀
 h = 5 ³₄ h

Distance between the two cities
= 5 ³₄ x 72
= ²³₄ x 72
= 414 km

Answer(s): (a) 60 km/h; (b) 414 km