At 9 a.m., Cindy and Tiffany raced off together from the starting point of a pathway. Cindy ran at an average speed of 2 m/s. Tiffany ran at an average speed of 4 m/s. Upon reaching the end of the pathway, Tiffany rested for 3 minutes. She then immediately ran back along the same route at 4 m/s. At 9.30 a.m., Cindy met Tiffany.
- Find the total distance covered by the two runners when they met each other. Express your answer in km.
- Find the length of the trail in km.
(a)
From 9 a.m. to 9.30 a.m. = 30 min
Duration that Cindy ran = 30 min
Duration that Tiffany ran = 30 - 3 = 27 min
1 min = 60 s
27 min = 27 x 60 = 1620 s
30 min = 30 x 60 = 1800 s
Distance that Cindy ran
= 2 x 1800
= 3600 m
Distance that Tiffany ran
= 4 x 1620
= 6480 m
Distance that Cindy and Tiffany ran
= 3600 + 6480
= 10080 m
1000 m = 1 km
10080 m = 10080 ÷ 1000 = 10.08 km
(b)
Length of the trail
= 10.08 ÷ 2
= 5.04 km
Answer(s): (a) 10.08 km; (b) 5.04 km