At 9 a.m., Penelope and Vanessa raced off together from the starting point of a route. Penelope ran at an average speed of 2 m/s. Vanessa ran at an average speed of 4 m/s. Upon reaching the end of the route, Vanessa rested for 3 minutes. She then immediately ran back along the same route at 4 m/s. At 9.25 a.m., Penelope met Vanessa.
- 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 9.25 a.m. = 25 min
Duration that Penelope ran = 25 min
Duration that Vanessa 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 Penelope ran
= 2 x 1500
= 3000 m
Distance that Vanessa ran
= 4 x 1320
= 5280 m
Distance that Penelope and Vanessa ran
= 3000 + 5280
= 8280 m
1000 m = 1 km
8280 m = 8280 ÷ 1000 = 8.28 km
(b)
Length of the trail
= 8.28 ÷ 2
= 4.14 km
Answer(s): (a) 8.28 km; (b) 4.14 km