Answer:
![147.6\:\mathrm](https://tex.z-dn.net/?f=147.6%5C%3A%5Cmathrm)
Step-by-step explanation:
The perimeter of a polygon is simply sum of the lengths of all sides of the polygon.
Therefore, we can find this polygon's perimeter by adding up the length of each of its sides:
![9.8+9.8+11.7+9.8+21.5+21+11.7+9.8+31.3+11.2=\boxed{147.6\:\mathrm{m}}](https://tex.z-dn.net/?f=9.8%2B9.8%2B11.7%2B9.8%2B21.5%2B21%2B11.7%2B9.8%2B31.3%2B11.2%3D%5Cboxed%7B147.6%5C%3A%5Cmathrm%7Bm%7D%7D)
Since there is a lot to keep track of, I'd recommend picking any side and moving clockwise/counter-clockwise until you get all sides.
Answer:
![\large\boxed{a_{10}=\dfrac{3}{110}}](https://tex.z-dn.net/?f=%5Clarge%5Cboxed%7Ba_%7B10%7D%3D%5Cdfrac%7B3%7D%7B110%7D%7D)
Step-by-step explanation:
Put <em>n = 10</em> to the equation ![a_n=\dfrac{3}{n(n+1)}](https://tex.z-dn.net/?f=a_n%3D%5Cdfrac%7B3%7D%7Bn%28n%2B1%29%7D)
![a_{10}=\dfrac{3}{10(10+1)}=\dfrac{3}{10(11)}=\dfrac{3}{110}](https://tex.z-dn.net/?f=a_%7B10%7D%3D%5Cdfrac%7B3%7D%7B10%2810%2B1%29%7D%3D%5Cdfrac%7B3%7D%7B10%2811%29%7D%3D%5Cdfrac%7B3%7D%7B110%7D)
I’m confused?? Do you just need 1/3 of 12? That’s 4 because 12 x 1 =12 and 12/3 is 4 lol
For this case we have:
If after 2 hours the marathon runner has traveled 22 kilometers we have:
2h -----------> 22km
Applying a rule of three, we can know the time it takes to run 42km. So, we have:
2h -----------> 22km
x -------------> 42km
Where "x" is the time it takes to travel 42km. Resolving we have:
![x = \frac {(42 * 2)} {22}](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%20%7B%2842%20%2A%202%29%7D%20%7B22%7D)
![x = \frac {84} {22}](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%20%7B84%7D%20%7B22%7D)
![x = \frac {42} {11}](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%20%7B42%7D%20%7B11%7D)
![x = 3.82 hours](https://tex.z-dn.net/?f=x%20%3D%203.82%20hours)
Thus, after 3.82 hours the marathon runner will travel 42km.
Answer:
3.82 hours