At 09 15, Irene left Town J and cycled towards Town K. Ivory left Town J and cycled towards Town K at 09 35. Ivory's cycling speed was 3 km/h faster than Irene. At 12 15, Ivory caught up with Irene. Find the cycling speed of each cyclist.
- Irene
- Ivory
(a)
Duration that Ivory cycled from 09 35 to 12 15
= 2
4060 = 2
23 h
Distance that Ivory cycled more than Irene
= 2
23 x 3
= 8 km
However, since Irene left 20 minutes earlier than Ivory and Ivory caught up with Irene, it means that Irene has cycled 8 km in 20 min.
1 h = 60 min
20 min = 20 ÷ 60 =
13 h
Irene's cycling speed
= 8 ÷
13 = 8 x
31 = 24 km/h
(b)
Ivory's cycling speed
= 24 + 3
= 27 km/h
Answer(s): (a) 24 km/h ; (b) 27 km/h
