At 07 15, Cathy left Town R and cycled towards Town S. Raeann left Town R and cycled towards Town S at 07 45. Raeann's cycling speed was 4 km/h faster than Cathy. At 10 15, Raeann caught up with Cathy. Find the cycling speed of each cyclist.

1. Cathy
2. Raeann

(a)
Duration that Raeann cycled from 07 45 to 10 15
= 2³⁰₆₀
= 2¹₂ h

Distance that Raeann cycled more than Cathy
= 2¹₂ x 4
= 10 km

However, since Cathy left 30 minutes earlier than Raeann and Raeann caught up with Cathy, it means that Cathy has cycled 10 km in 30 min.

1 h = 60 min 
30 min = 30 ÷ 60 = ¹₂ h

Cathy's cycling speed
= 10 ÷ ¹₂
= 10 x ²₁
= 20 km/h

(b)
Raeann's cycling speed
= 20 + 4
= 24 km/h

Answer(s): (a) 20 km/h ; (b) 24 km/h