At 8 a.m., Elijah started from City T and travelled towards City U and his speed remained constant throughout. At 10 a.m., Yoko started her journey from City T towards City U at an average speed of 81 km/h. Yoko overtook Elijah at 2 p.m. After overtaking, Yoko carried on her journey at the same average speed and reached at City U at 5:40 p.m.

1. Find Elijah's average speed in km/h.
2. What is the distance between the two cities?

(a)
From 10 a.m. to 2 p.m. = 4 h

Distance that Yoko had travelled until Yoko overtook Elijah
= 4 x 81
= 324 km

From 8 a.m. to 2 p.m. = 6 h

Elijah's average speed
= 324 ÷ 6
= 54 km/h

(b)
From 10 a.m. to 5:40 p.m. = 7 h 40 min

1 h = 60 min
7 h 40 min = 7 ⁴⁰ ₆₀
 h = 7 ²₃ h

Distance between the two cities
= 7 ²₃ x 81
= ²³₃ x 81
= 621 km

Answer(s): (a) 54 km/h; (b) 621 km