At 9 a.m., Tammy and Xylia raced off together from the starting point of a course. Tammy ran at an average speed of 2 m/s. Xylia ran at an average speed of 4 m/s. Upon reaching the end of the course, Xylia rested for 4 minutes. She then immediately ran back along the same route at 4 m/s. At 9.50 a.m., Tammy met Xylia.

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 Tammy ran = 50 min
Duration that Xylia 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 Tammy ran
= 2 x 3000
= 6000 m

Distance that Xylia ran
= 4 x 2760
= 11040 m

Distance that Tammy and Xylia ran
= 6000 + 11040
= 17040 m

1000 m = 1 km

17040 m = 17040 ÷ 1000 = 17.04 km

(b)
Length of the trail
= 17.04 ÷ 2
= 8.52 km

Answer(s): (a) 17.04 km; (b) 8.52 km