At 10 a.m., Kimberly and Anna raced off together from the starting point of a pathway. Kimberly ran at an average speed of 1 m/s. Anna ran at an average speed of 2 m/s. Upon reaching the end of the pathway, Anna rested for 5 minutes. She then immediately ran back along the same route at 2 m/s. At 10.50 a.m., Kimberly met Anna.

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 10.50 a.m. = 50 min

Duration that Kimberly ran = 50 min
Duration that Anna ran = 50 -  5 = 45 min

1 min = 60 s

45 min = 45 x 60 = 2700 s
50 min = 50 x 60 = 3000 s

Distance that Kimberly ran
= 1 x 3000
= 3000 m

Distance that Anna ran
= 2 x 2700
= 5400 m

Distance that Kimberly and Anna ran
= 3000 + 5400
= 8400 m

1000 m = 1 km

8400 m = 8400 ÷ 1000 = 8.4 km

(b)
Length of the trail
= 8.4 ÷ 2
= 4.2 km

Answer(s): (a) 8.4 km; (b) 4.2 km