At 9 a.m., Tiffany and Raeann raced off together from the starting point of a path. Tiffany ran at an average speed of 2 m/s. Raeann ran at an average speed of 4 m/s. Upon reaching the end of the path, Raeann rested for 3 minutes. She then immediately ran back along the same route at 4 m/s. At 9.50 a.m., Tiffany met Raeann.

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 9.50 a.m. = 50 min

Duration that Tiffany ran = 50 min
Duration that Raeann ran = 50 -  3 = 47 min

1 min = 60 s

47 min = 47 x 60 = 2820 s
50 min = 50 x 60 = 3000 s

Distance that Tiffany ran
= 2 x 3000
= 6000 m

Distance that Raeann ran
= 4 x 2820
= 11280 m

Distance that Tiffany and Raeann ran
= 6000 + 11280
= 17280 m

1000 m = 1 km

17280 m = 17280 ÷ 1000 = 17.28 km

(b)
Length of the trail
= 17.28 ÷ 2
= 8.64 km

Answer(s): (a) 17.28 km; (b) 8.64 km