At 06 20, Julie left Town C and cycled towards Town D. Emily left Town C and cycled towards Town D at 06 50. Emily's cycling speed was 4 km/h faster than Julie. At 11 20, Emily caught up with Julie. Find the cycling speed of each cyclist.
- Julie
- Emily
(a)
Duration that Emily cycled from 06 50 to 11 20
= 4
3060 = 4
12 h
Distance that Emily cycled more than Julie
= 4
12 x 4
= 18 km
However, since Julie left 30 minutes earlier than Emily and Emily caught up with Julie, it means that Julie has cycled 18 km in 30 min.
1 h = 60 min
30 min = 30 ÷ 60 =
12 h
Julie's cycling speed
= 18 ÷
12 = 18 x
21 = 36 km/h
(b)
Emily's cycling speed
= 36 + 4
= 40 km/h
Answer(s): (a) 36 km/h ; (b) 40 km/h
