At 09 35, Gwen left Town W and cycled towards Town X. Betty left Town W and cycled towards Town X at 09 50. Betty's cycling speed was 4 km/h faster than Gwen. At 11 35, Betty caught up with Gwen. Find the cycling speed of each cyclist.
- Gwen
- Betty
(a)
Duration that Betty cycled from 09 50 to 11 35
= 1
4560 = 1
34 h
Distance that Betty cycled more than Gwen
= 1
34 x 4
= 7 km
However, since Gwen left 15 minutes earlier than Betty and Betty caught up with Gwen, it means that Gwen has cycled 7 km in 15 min.
1 h = 60 min
15 min = 15 ÷ 60 =
14 h
Gwen's cycling speed
= 7 ÷
14 = 7 x
41 = 28 km/h
(b)
Betty's cycling speed
= 28 + 4
= 32 km/h
Answer(s): (a) 28 km/h ; (b) 32 km/h
