At 10 a.m., Sabrina and Ivory raced off together from the starting point of a track. Sabrina ran at an average speed of 2 m/s. Ivory ran at an average speed of 3 m/s. Upon reaching the end of the track, Ivory rested for 5 minutes. She then immediately ran back along the same route at 3 m/s. At 10.25 a.m., Sabrina met Ivory.

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 10.25 a.m. = 25 min

Duration that Sabrina ran = 25 min
Duration that Ivory ran = 25 -  5 = 20 min

1 min = 60 s

20 min = 20 x 60 = 1200 s
25 min = 25 x 60 = 1500 s

Distance that Sabrina ran
= 2 x 1500
= 3000 m

Distance that Ivory ran
= 3 x 1200
= 3600 m

Distance that Sabrina and Ivory ran
= 3000 + 3600
= 6600 m

1000 m = 1 km

6600 m = 6600 ÷ 1000 = 6.6 km

(b)
Length of the trail
= 6.6 ÷ 2
= 3.3 km

Answer(s): (a) 6.6 km; (b) 3.3 km