At 9 a.m., Emma and Winnie raced off together from the starting point of a route. Emma ran at an average speed of 1 m/s. Winnie ran at an average speed of 3 m/s. Upon reaching the end of the route, Winnie rested for 6 minutes. She then immediately ran back along the same route at 3 m/s. At 9.45 a.m., Emma met Winnie.

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 9 a.m. to 9.45 a.m. = 45 min

Duration that Emma ran = 45 min
Duration that Winnie ran = 45 -  6 = 39 min

1 min = 60 s

39 min = 39 x 60 = 2340 s
45 min = 45 x 60 = 2700 s

Distance that Emma ran
= 1 x 2700
= 2700 m

Distance that Winnie ran
= 3 x 2340
= 7020 m

Distance that Emma and Winnie ran
= 2700 + 7020
= 9720 m

1000 m = 1 km

9720 m = 9720 ÷ 1000 = 9.72 km

(b)
Length of the trail
= 9.72 ÷ 2
= 4.86 km

Answer(s): (a) 9.72 km; (b) 4.86 km