At 10 a.m., Xuan and Joelle raced off together from the starting point of a pathway. Xuan ran at an average speed of 2 m/s. Joelle ran at an average speed of 4 m/s. Upon reaching the end of the pathway, Joelle rested for 6 minutes. She then immediately ran back along the same route at 4 m/s. At 10.35 a.m., Xuan met Joelle.
- Find the total distance covered by the two runners when they met each other. Express your answer in km.
- Find the length of the trail in km.
(a)
From 10 a.m. to 10.35 a.m. = 35 min
Duration that Xuan ran = 35 min
Duration that Joelle ran = 35 - 6 = 29 min
1 min = 60 s
29 min = 29 x 60 = 1740 s
35 min = 35 x 60 = 2100 s
Distance that Xuan ran
= 2 x 2100
= 4200 m
Distance that Joelle ran
= 4 x 1740
= 6960 m
Distance that Xuan and Joelle ran
= 4200 + 6960
= 11160 m
1000 m = 1 km
11160 m = 11160 ÷ 1000 = 11.16 km
(b)
Length of the trail
= 11.16 ÷ 2
= 5.58 km
Answer(s): (a) 11.16 km; (b) 5.58 km