Respuesta :
Answer:
21.6 km
Step-by-step explanation:
distance swam on day 2: 6.48+0.720 = 7.2 km
distance swam on day 3: 7.2*3 = 21.6 km
Let x = Day 1
Day 2 = x + 0.72
Day 3 = (x + 0.72)(3)
Total km = 6.48 km
6.48 = x + (x + 0.72) + ((x + 0.72)(3))
6.48 = x + x + 0.72 + 3x + 2.16
6.48 - 2.16 - 0.72 = 5x
5x = 3.6
x = 0.72
Day 3:
(x + 0.72)(3)
(0.72 + 0.72)(3)
(1.44)(3)
4.32
Nils swam 4.32 km on Day 3.
Day 2 = x + 0.72
Day 3 = (x + 0.72)(3)
Total km = 6.48 km
6.48 = x + (x + 0.72) + ((x + 0.72)(3))
6.48 = x + x + 0.72 + 3x + 2.16
6.48 - 2.16 - 0.72 = 5x
5x = 3.6
x = 0.72
Day 3:
(x + 0.72)(3)
(0.72 + 0.72)(3)
(1.44)(3)
4.32
Nils swam 4.32 km on Day 3.