At 7 a.m., Japheth started from City K and travelled towards City L and his speed remained constant throughout. At 10 a.m., Irene started her journey from City K towards City L at an average speed of 88 km/h. Irene overtook Japheth at 1 p.m. After overtaking, Irene carried on her journey at the same average speed and reached at City L at 5:30 p.m.

1. Find Japheth'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 Irene had travelled until Irene overtook Japheth
= 3 x 88
= 264 km

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

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

(b)
From 10 a.m. to 5:30 p.m. = 7 h 30 min

1 h = 60 min
7 h 30 min = 7 ³⁰ ₆₀
 h = 7 ¹₂ h

Distance between the two cities
= 7 ¹₂ x 88
= ¹⁵₂ x 88
= 660 km

Answer(s): (a) 44 km/h; (b) 660 km