At 9 a.m., Nick started from City L and travelled towards City M and his speed remained constant throughout. At 10 a.m., Linda started her journey from City L towards City M at an average speed of 78 km/h. Linda overtook Nick at 3 p.m. After overtaking, Linda carried on her journey at the same average speed and reached at City M at 6:50 p.m.

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

(a)
From 10 a.m. to 3 p.m. = 5 h

Distance that Linda had travelled until Linda overtook Nick
= 5 x 78
= 390 km

From 9 a.m. to 3 p.m. = 6 h

Nick's average speed
= 390 ÷ 6
= 65 km/h

(b)
From 10 a.m. to 6:50 p.m. = 8 h 50 min

1 h = 60 min
8 h 50 min = 8 ⁵⁰ ₆₀
 h = 8 ⁵₆ h

Distance between the two cities
= 8 ⁵₆ x 78
= ⁵³₆ x 78
= 689 km

Answer(s): (a) 65 km/h; (b) 689 km