At 7 a.m., Gem and Kathy raced off together from the starting point of a path. Gem ran at an average speed of 3 m/s. Kathy ran at an average speed of 4 m/s. Upon reaching the end of the path, Kathy rested for 3 minutes. She then immediately ran back along the same route at 4 m/s. At 7.25 a.m., Gem met Kathy.

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 7.25 a.m. = 25 min

Duration that Gem ran = 25 min
Duration that Kathy ran = 25 -  3 = 22 min

1 min = 60 s

22 min = 22 x 60 = 1320 s
25 min = 25 x 60 = 1500 s

Distance that Gem ran
= 3 x 1500
= 4500 m

Distance that Kathy ran
= 4 x 1320
= 5280 m

Distance that Gem and Kathy ran
= 4500 + 5280
= 9780 m

1000 m = 1 km

9780 m = 9780 ÷ 1000 = 9.78 km

(b)
Length of the trail
= 9.78 ÷ 2
= 4.89 km

Answer(s): (a) 9.78 km; (b) 4.89 km