At 7 a.m., Eva and Emily raced off together from the starting point of a track. Eva ran at an average speed of 1 m/s. Emily ran at an average speed of 4 m/s. Upon reaching the end of the track, Emily rested for 3 minutes. She then immediately ran back along the same route at 4 m/s. At 7.25 a.m., Eva met Emily.
- 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 7 a.m. to 7.25 a.m. = 25 min
Duration that Eva ran = 25 min
Duration that Emily ran = 25 - 3 = 22 min
1 min = 60 s
22 min = 22 x 60 = 1320 s
25 min = 25 x 60 = 1500 s
Distance that Eva ran
= 1 x 1500
= 1500 m
Distance that Emily ran
= 4 x 1320
= 5280 m
Distance that Eva and Emily ran
= 1500 + 5280
= 6780 m
1000 m = 1 km
6780 m = 6780 ÷ 1000 = 6.78 km
(b)
Length of the trail
= 6.78 ÷ 2
= 3.39 km
Answer(s): (a) 6.78 km; (b) 3.39 km