At 07 15, Rachel left Town A and cycled towards Town B. Dana left Town A and cycled towards Town B at 07 45. Dana's cycling speed was 4 km/h faster than Rachel. At 12 15, Dana caught up with Rachel. Find the cycling speed of each cyclist.
- Rachel
- Dana
(a)
Duration that Dana cycled from 07 45 to 12 15
= 4
3060 = 4
12 h
Distance that Dana cycled more than Rachel
= 4
12 x 4
= 18 km
However, since Rachel left 30 minutes earlier than Dana and Dana caught up with Rachel, it means that Rachel has cycled 18 km in 30 min.
1 h = 60 min
30 min = 30 ÷ 60 =
12 h
Rachel's cycling speed
= 18 ÷
12 = 18 x
21 = 36 km/h
(b)
Dana's cycling speed
= 36 + 4
= 40 km/h
Answer(s): (a) 36 km/h ; (b) 40 km/h
