At 9 a.m., Fanny and Gwen raced off together from the starting point of a route. Fanny ran at an average speed of 1 m/s. Gwen ran at an average speed of 4 m/s. Upon reaching the end of the route, Gwen rested for 4 minutes. She then immediately ran back along the same route at 4 m/s. At 9.50 a.m., Fanny met Gwen.

1. Find the total distance covered by the two runners when they met each other. Express your answer in km.
2. Find the length of the trail in km.

(a)
From 9 a.m. to 9.50 a.m. = 50 min

Duration that Fanny ran = 50 min
Duration that Gwen ran = 50 -  4 = 46 min

1 min = 60 s

46 min = 46 x 60 = 2760 s
50 min = 50 x 60 = 3000 s

Distance that Fanny ran
= 1 x 3000
= 3000 m

Distance that Gwen ran
= 4 x 2760
= 11040 m

Distance that Fanny and Gwen ran
= 3000 + 11040
= 14040 m

1000 m = 1 km

14040 m = 14040 ÷ 1000 = 14.04 km

(b)
Length of the trail
= 14.04 ÷ 2
= 7.02 km

Answer(s): (a) 14.04 km; (b) 7.02 km