At 10 a.m., Hazel and Marion raced off together from the starting point of a pathway. Hazel ran at an average speed of 3 m/s. Marion ran at an average speed of 4 m/s. Upon reaching the end of the pathway, Marion rested for 4 minutes. She then immediately ran back along the same route at 4 m/s. At 10.35 a.m., Hazel met Marion.

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 10 a.m. to 10.35 a.m. = 35 min

Duration that Hazel ran = 35 min
Duration that Marion ran = 35 -  4 = 31 min

1 min = 60 s

31 min = 31 x 60 = 1860 s
35 min = 35 x 60 = 2100 s

Distance that Hazel ran
= 3 x 2100
= 6300 m

Distance that Marion ran
= 4 x 1860
= 7440 m

Distance that Hazel and Marion ran
= 6300 + 7440
= 13740 m

1000 m = 1 km

13740 m = 13740 ÷ 1000 = 13.74 km

(b)
Length of the trail
= 13.74 ÷ 2
= 6.87 km

Answer(s): (a) 13.74 km; (b) 6.87 km