At 8 a.m., Cathy and Linda raced off together from the starting point of a course. Cathy ran at an average speed of 3 m/s. Linda ran at an average speed of 4 m/s. Upon reaching the end of the course, Linda rested for 4 minutes. She then immediately ran back along the same route at 4 m/s. At 8.30 a.m., Cathy met Linda.
- 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 8 a.m. to 8.30 a.m. = 30 min
Duration that Cathy ran = 30 min
Duration that Linda ran = 30 - 4 = 26 min
1 min = 60 s
26 min = 26 x 60 = 1560 s
30 min = 30 x 60 = 1800 s
Distance that Cathy ran
= 3 x 1800
= 5400 m
Distance that Linda ran
= 4 x 1560
= 6240 m
Distance that Cathy and Linda ran
= 5400 + 6240
= 11640 m
1000 m = 1 km
11640 m = 11640 ÷ 1000 = 11.64 km
(b)
Length of the trail
= 11.64 ÷ 2
= 5.82 km
Answer(s): (a) 11.64 km; (b) 5.82 km