At 7 a.m., Lucy and Irene raced off together from the starting point of a pathway. Lucy ran at an average speed of 3 m/s. Irene ran at an average speed of 4 m/s. Upon reaching the end of the pathway, Irene rested for 6 minutes. She then immediately ran back along the same route at 4 m/s. At 7.25 a.m., Lucy met Irene.
- 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 Lucy ran = 25 min
Duration that Irene ran = 25 - 6 = 19 min
1 min = 60 s
19 min = 19 x 60 = 1140 s
25 min = 25 x 60 = 1500 s
Distance that Lucy ran
= 3 x 1500
= 4500 m
Distance that Irene ran
= 4 x 1140
= 4560 m
Distance that Lucy and Irene ran
= 4500 + 4560
= 9060 m
1000 m = 1 km
9060 m = 9060 ÷ 1000 = 9.06 km
(b)
Length of the trail
= 9.06 ÷ 2
= 4.53 km
Answer(s): (a) 9.06 km; (b) 4.53 km