At 9 a.m., Min and Cathy raced off together from the starting point of a course. Min ran at an average speed of 1 m/s. Cathy ran at an average speed of 2 m/s. Upon reaching the end of the course, Cathy rested for 5 minutes. She then immediately ran back along the same route at 2 m/s. At 9.35 a.m., Min met Cathy.

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 9 a.m. to 9.35 a.m. = 35 min

Duration that Min ran = 35 min
Duration that Cathy ran = 35 -  5 = 30 min

1 min = 60 s

30 min = 30 x 60 = 1800 s
35 min = 35 x 60 = 2100 s

Distance that Min ran
= 1 x 2100
= 2100 m

Distance that Cathy ran
= 2 x 1800
= 3600 m

Distance that Min and Cathy ran
= 2100 + 3600
= 5700 m

1000 m = 1 km

5700 m = 5700 ÷ 1000 = 5.7 km

(b)
Length of the trail
= 5.7 ÷ 2
= 2.85 km

Answer(s): (a) 5.7 km; (b) 2.85 km