At 7 a.m., Betty and Gwen raced off together from the starting point of a path. Betty ran at an average speed of 1 m/s. Gwen ran at an average speed of 3 m/s. Upon reaching the end of the path, Gwen rested for 6 minutes. She then immediately ran back along the same route at 3 m/s. At 7.30 a.m., Betty met Gwen.

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 7.30 a.m. = 30 min

Duration that Betty ran = 30 min
Duration that Gwen ran = 30 -  6 = 24 min

1 min = 60 s

24 min = 24 x 60 = 1440 s
30 min = 30 x 60 = 1800 s

Distance that Betty ran
= 1 x 1800
= 1800 m

Distance that Gwen ran
= 3 x 1440
= 4320 m

Distance that Betty and Gwen ran
= 1800 + 4320
= 6120 m

1000 m = 1 km

6120 m = 6120 ÷ 1000 = 6.12 km

(b)
Length of the trail
= 6.12 ÷ 2
= 3.06 km

Answer(s): (a) 6.12 km; (b) 3.06 km