At 7 a.m., Jane and Lucy raced off together from the starting point of a course. Jane ran at an average speed of 1 m/s. Lucy ran at an average speed of 2 m/s. Upon reaching the end of the course, Lucy rested for 4 minutes. She then immediately ran back along the same route at 2 m/s. At 7.35 a.m., Jane met Lucy.

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 7 a.m. to 7.35 a.m. = 35 min

Duration that Jane ran = 35 min
Duration that Lucy 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 Jane ran
= 1 x 2100
= 2100 m

Distance that Lucy ran
= 2 x 1860
= 3720 m

Distance that Jane and Lucy ran
= 2100 + 3720
= 5820 m

1000 m = 1 km

5820 m = 5820 ÷ 1000 = 5.82 km

(b)
Length of the trail
= 5.82 ÷ 2
= 2.91 km

Answer(s): (a) 5.82 km; (b) 2.91 km