At 11 a.m., Kylie and Hilda raced off together from the starting point of a course. Kylie ran at an average speed of 2 m/s. Hilda ran at an average speed of 4 m/s. Upon reaching the end of the course, Hilda rested for 4 minutes. She then immediately ran back along the same route at 4 m/s. At 11.30 a.m., Kylie met Hilda.

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 11 a.m. to 11.30 a.m. = 30 min

Duration that Kylie ran = 30 min
Duration that Hilda ran = 30 -  4 = 26 min

1 min = 60 s

26 min = 26 x 60 = 1560 s
30 min = 30 x 60 = 1800 s

Distance that Kylie ran
= 2 x 1800
= 3600 m

Distance that Hilda ran
= 4 x 1560
= 6240 m

Distance that Kylie and Hilda ran
= 3600 + 6240
= 9840 m

1000 m = 1 km

9840 m = 9840 ÷ 1000 = 9.84 km

(b)
Length of the trail
= 9.84 ÷ 2
= 4.92 km

Answer(s): (a) 9.84 km; (b) 4.92 km