At 7 a.m., Sabrina and Jaslyn raced off together from the starting point of a pathway. Sabrina ran at an average speed of 2 m/s. Jaslyn ran at an average speed of 4 m/s. Upon reaching the end of the pathway, Jaslyn rested for 4 minutes. She then immediately ran back along the same route at 4 m/s. At 7.45 a.m., Sabrina met Jaslyn.

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 7.45 a.m. = 45 min

Duration that Sabrina ran = 45 min
Duration that Jaslyn ran = 45 -  4 = 41 min

1 min = 60 s

41 min = 41 x 60 = 2460 s
45 min = 45 x 60 = 2700 s

Distance that Sabrina ran
= 2 x 2700
= 5400 m

Distance that Jaslyn ran
= 4 x 2460
= 9840 m

Distance that Sabrina and Jaslyn ran
= 5400 + 9840
= 15240 m

1000 m = 1 km

15240 m = 15240 ÷ 1000 = 15.24 km

(b)
Length of the trail
= 15.24 ÷ 2
= 7.62 km

Answer(s): (a) 15.24 km; (b) 7.62 km