At 10 a.m., Nora and Zara raced off together from the starting point of a pathway. Nora ran at an average speed of 1 m/s. Zara ran at an average speed of 4 m/s. Upon reaching the end of the pathway, Zara rested for 3 minutes. She then immediately ran back along the same route at 4 m/s. At 10.50 a.m., Nora met Zara.
- 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 10 a.m. to 10.50 a.m. = 50 min
Duration that Nora ran = 50 min
Duration that Zara ran = 50 - 3 = 47 min
1 min = 60 s
47 min = 47 x 60 = 2820 s
50 min = 50 x 60 = 3000 s
Distance that Nora ran
= 1 x 3000
= 3000 m
Distance that Zara ran
= 4 x 2820
= 11280 m
Distance that Nora and Zara ran
= 3000 + 11280
= 14280 m
1000 m = 1 km
14280 m = 14280 ÷ 1000 = 14.28 km
(b)
Length of the trail
= 14.28 ÷ 2
= 7.14 km
Answer(s): (a) 14.28 km; (b) 7.14 km