At 09 15, Usha left Town A and cycled towards Town B. Cathy left Town A and cycled towards Town B at 09 45. Cathy's cycling speed was 2 km/h faster than Usha. At 14 15, Cathy caught up with Usha. Find the cycling speed of each cyclist.
- Usha
- Cathy
(a)
Duration that Cathy cycled from 09 45 to 14 15
= 4
3060 = 4
12 h
Distance that Cathy cycled more than Usha
= 4
12 x 2
= 9 km
However, since Usha left 30 minutes earlier than Cathy and Cathy caught up with Usha, it means that Usha has cycled 9 km in 30 min.
1 h = 60 min
30 min = 30 ÷ 60 =
12 h
Usha's cycling speed
= 9 ÷
12 = 9 x
21 = 18 km/h
(b)
Cathy's cycling speed
= 18 + 2
= 20 km/h
Answer(s): (a) 18 km/h ; (b) 20 km/h
