At 7 a.m., Albert started from City N and travelled towards City P and his speed remained constant throughout. At 10 a.m., Eva started her journey from City N towards City P at an average speed of 78 km/h. Eva overtook Albert at 1 p.m. After overtaking, Eva carried on her journey at the same average speed and reached at City P at 3:20 p.m.

1. Find Albert'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 Eva had travelled until Eva overtook Albert
= 3 x 78
= 234 km

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

Albert's average speed
= 234 ÷ 6
= 39 km/h

(b)
From 10 a.m. to 3:20 p.m. = 5 h 20 min

1 h = 60 min
5 h 20 min = 5 ²⁰ ₆₀
 h = 5 ¹₃ h

Distance between the two cities
= 5 ¹₃ x 78
= ¹⁶₃ x 78
= 416 km

Answer(s): (a) 39 km/h; (b) 416 km