At 11 a.m., Tammy and Zara raced off together from the starting point of a pathway. Tammy ran at an average speed of 1 m/s. Zara ran at an average speed of 4 m/s. Upon reaching the end of the pathway, Zara rested for 3 minutes. She then immediately ran back along the same route at 4 m/s. At 11.35 a.m., Tammy met Zara.

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 11 a.m. to 11.35 a.m. = 35 min

Duration that Tammy ran = 35 min
Duration that Zara ran = 35 -  3 = 32 min

1 min = 60 s

32 min = 32 x 60 = 1920 s
35 min = 35 x 60 = 2100 s

Distance that Tammy ran
= 1 x 2100
= 2100 m

Distance that Zara ran
= 4 x 1920
= 7680 m

Distance that Tammy and Zara ran
= 2100 + 7680
= 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