At 8 a.m., Tina and Jen raced off together from the starting point of a track. Tina ran at an average speed of 2 m/s. Jen ran at an average speed of 4 m/s. Upon reaching the end of the track, Jen rested for 6 minutes. She then immediately ran back along the same route at 4 m/s. At 8.40 a.m., Tina met Jen.
- 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 8.40 a.m. = 40 min
Duration that Tina ran = 40 min
Duration that Jen ran = 40 - 6 = 34 min
1 min = 60 s
34 min = 34 x 60 = 2040 s
40 min = 40 x 60 = 2400 s
Distance that Tina ran
= 2 x 2400
= 4800 m
Distance that Jen ran
= 4 x 2040
= 8160 m
Distance that Tina and Jen ran
= 4800 + 8160
= 12960 m
1000 m = 1 km
12960 m = 12960 ÷ 1000 = 12.96 km
(b)
Length of the trail
= 12.96 ÷ 2
= 6.48 km
Answer(s): (a) 12.96 km; (b) 6.48 km