At 7 a.m., Warren started from City C and travelled towards City D and his speed remained constant throughout. At 9 a.m., Joelle started her journey from City C towards City D at an average speed of 66 km/h. Joelle overtook Warren at 1 p.m. After overtaking, Joelle carried on her journey at the same average speed and reached at City D at 1:40 p.m.

1. Find Warren'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 Joelle had travelled until Joelle overtook Warren
= 4 x 66
= 264 km

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

Warren's average speed
= 264 ÷ 6
= 44 km/h

(b)
From 9 a.m. to 1:40 p.m. = 4 h 40 min

1 h = 60 min
4 h 40 min = 4 ⁴⁰ ₆₀
 h = 4 ²₃ h

Distance between the two cities
= 4 ²₃ x 66
= ¹⁴₃ x 66
= 308 km

Answer(s): (a) 44 km/h; (b) 308 km