At 7 a.m., Jane and Cindy raced off together from the starting point of a route. Jane ran at an average speed of 2 m/s. Cindy ran at an average speed of 4 m/s. Upon reaching the end of the route, Cindy rested for 5 minutes. She then immediately ran back along the same route at 4 m/s. At 7.40 a.m., Jane met Cindy.

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 7.40 a.m. = 40 min

Duration that Jane ran = 40 min
Duration that Cindy ran = 40 -  5 = 35 min

1 min = 60 s

35 min = 35 x 60 = 2100 s
40 min = 40 x 60 = 2400 s

Distance that Jane ran
= 2 x 2400
= 4800 m

Distance that Cindy ran
= 4 x 2100
= 8400 m

Distance that Jane and Cindy ran
= 4800 + 8400
= 13200 m

1000 m = 1 km

13200 m = 13200 ÷ 1000 = 13.2 km

(b)
Length of the trail
= 13.2 ÷ 2
= 6.6 km

Answer(s): (a) 13.2 km; (b) 6.6 km