At 9 a.m., Ahmad started from City Y and travelled towards City Z and his speed remained constant throughout. At 10 a.m., Usha started her journey from City Y towards City Z at an average speed of 88 km/h. Usha overtook Ahmad at 1 p.m. After overtaking, Usha carried on her journey at the same average speed and reached at City Z at 4:15 p.m.

1. Find Ahmad'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 Usha had travelled until Usha overtook Ahmad
= 3 x 88
= 264 km

From 9 a.m. to 1 p.m. = 4 h

Ahmad's average speed
= 264 ÷ 4
= 66 km/h

(b)
From 10 a.m. to 4:15 p.m. = 6 h 15 min

1 h = 60 min
6 h 15 min = 6 ¹⁵ ₆₀
 h = 6 ¹₄ h

Distance between the two cities
= 6 ¹₄ x 88
= ²⁵₄ x 88
= 550 km

Answer(s): (a) 66 km/h; (b) 550 km