At 10 a.m., Min and Dana raced off together from the starting point of a route. Min ran at an average speed of 3 m/s. Dana ran at an average speed of 4 m/s. Upon reaching the end of the route, Dana rested for 3 minutes. She then immediately ran back along the same route at 4 m/s. At 10.30 a.m., Min met Dana.

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 10.30 a.m. = 30 min

Duration that Min ran = 30 min
Duration that Dana ran = 30 -  3 = 27 min

1 min = 60 s

27 min = 27 x 60 = 1620 s
30 min = 30 x 60 = 1800 s

Distance that Min ran
= 3 x 1800
= 5400 m

Distance that Dana ran
= 4 x 1620
= 6480 m

Distance that Min and Dana ran
= 5400 + 6480
= 11880 m

1000 m = 1 km

11880 m = 11880 ÷ 1000 = 11.88 km

(b)
Length of the trail
= 11.88 ÷ 2
= 5.94 km

Answer(s): (a) 11.88 km; (b) 5.94 km