Answer:

Step-by-step explanation:
We have:

And we want to find B’(6).
So, we will need to find B(t) first. To do so, we will take the derivative of both sides with respect to x. Hence:
![\displaystyle B^\prime(t)=\frac{d}{dt}[24.6\sin(\frac{\pi t}{10})(8-t)]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20B%5E%5Cprime%28t%29%3D%5Cfrac%7Bd%7D%7Bdt%7D%5B24.6%5Csin%28%5Cfrac%7B%5Cpi%20t%7D%7B10%7D%29%288-t%29%5D)
We can move the constant outside:
![\displaystyle B^\prime(t)=24.6\frac{d}{dt}[\sin(\frac{\pi t}{10})(8-t)]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20B%5E%5Cprime%28t%29%3D24.6%5Cfrac%7Bd%7D%7Bdt%7D%5B%5Csin%28%5Cfrac%7B%5Cpi%20t%7D%7B10%7D%29%288-t%29%5D)
Now, we will utilize the product rule. The product rule is:

We will let:

Then:

(The derivative of u was determined using the chain rule.)
Then it follows that:
![\displaystyle \begin{aligned} B^\prime(t)&=24.6\frac{d}{dt}[\sin(\frac{\pi t}{10})(8-t)] \\ \\ &=24.6[(\frac{\pi}{10}\cos(\frac{\pi t}{10}))(8-t) - \sin(\frac{\pi t}{10})] \end{aligned}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cbegin%7Baligned%7D%20B%5E%5Cprime%28t%29%26%3D24.6%5Cfrac%7Bd%7D%7Bdt%7D%5B%5Csin%28%5Cfrac%7B%5Cpi%20t%7D%7B10%7D%29%288-t%29%5D%20%5C%5C%20%5C%5C%20%26%3D24.6%5B%28%5Cfrac%7B%5Cpi%7D%7B10%7D%5Ccos%28%5Cfrac%7B%5Cpi%20t%7D%7B10%7D%29%29%288-t%29%20-%20%5Csin%28%5Cfrac%7B%5Cpi%20t%7D%7B10%7D%29%5D%20%5Cend%7Baligned%7D)
Therefore:
![\displaystyle B^\prime(6) =24.6[(\frac{\pi}{10}\cos(\frac{\pi (6)}{10}))(8-(6))- \sin(\frac{\pi (6)}{10})]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20B%5E%5Cprime%286%29%20%3D24.6%5B%28%5Cfrac%7B%5Cpi%7D%7B10%7D%5Ccos%28%5Cfrac%7B%5Cpi%20%286%29%7D%7B10%7D%29%29%288-%286%29%29-%20%5Csin%28%5Cfrac%7B%5Cpi%20%286%29%7D%7B10%7D%29%5D)
By simplification:
![\displaystyle B^\prime(6)=24.6 [\frac{\pi}{10}\cos(\frac{3\pi}{5})(2)-\sin(\frac{3\pi}{5})] \approx -28.17](https://tex.z-dn.net/?f=%5Cdisplaystyle%20B%5E%5Cprime%286%29%3D24.6%20%5B%5Cfrac%7B%5Cpi%7D%7B10%7D%5Ccos%28%5Cfrac%7B3%5Cpi%7D%7B5%7D%29%282%29-%5Csin%28%5Cfrac%7B3%5Cpi%7D%7B5%7D%29%5D%20%5Capprox%20-28.17)
So, the slope of the tangent line to the point (6, B(6)) is -28.17.
x = total amount split between Adam and Tom.
since we know the total amount split between both in a 18 : 17 ratio is "x", let's divide "x" by (18 + 17) and distribute accordingly to get the amount of each.
![\stackrel{Adam~received}{18\cdot \cfrac{x}{18+17}}\qquad \qquad \stackrel{Tom~received}{17\cdot \cfrac{x}{18+17}} \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{since we know that Adam got "5" more}}{ \stackrel{Adam}{18\cdot \cfrac{x}{18+17}}~~ = ~~\stackrel{Tom}{17\cdot \cfrac{x}{18+17}~~ + ~~5} }\qquad \implies \qquad \cfrac{18x}{35}~~ + ~~\cfrac{17x}{35}+5](https://tex.z-dn.net/?f=%5Cstackrel%7BAdam~received%7D%7B18%5Ccdot%20%5Ccfrac%7Bx%7D%7B18%2B17%7D%7D%5Cqquad%20%5Cqquad%20%5Cstackrel%7BTom~received%7D%7B17%5Ccdot%20%5Ccfrac%7Bx%7D%7B18%2B17%7D%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Bsince%20we%20know%20that%20Adam%20got%20%225%22%20more%7D%7D%7B%20%5Cstackrel%7BAdam%7D%7B18%5Ccdot%20%5Ccfrac%7Bx%7D%7B18%2B17%7D%7D~~%20%3D%20~~%5Cstackrel%7BTom%7D%7B17%5Ccdot%20%5Ccfrac%7Bx%7D%7B18%2B17%7D~~%20%2B%20~~5%7D%20%7D%5Cqquad%20%5Cimplies%20%5Cqquad%20%5Ccfrac%7B18x%7D%7B35%7D~~%20%2B%20~~%5Ccfrac%7B17x%7D%7B35%7D%2B5)
![\stackrel{\textit{multiplying both sides by }\stackrel{LCD}{35}}{35\left( \cfrac{18x}{35} \right)~~ = ~~35\left( \cfrac{17x}{35}+5 \right)}\implies 18x~~ = ~~17x+175\implies \boxed{x =175} \\\\[-0.35em] ~\dotfill\\\\ \stackrel{Tom~received}{17\cdot \cfrac{x}{18+17}}\implies \cfrac{17(175)}{35}\implies \blacktriangleright 85 \blacktriangleleft](https://tex.z-dn.net/?f=%5Cstackrel%7B%5Ctextit%7Bmultiplying%20both%20sides%20by%20%7D%5Cstackrel%7BLCD%7D%7B35%7D%7D%7B35%5Cleft%28%20%5Ccfrac%7B18x%7D%7B35%7D%20%5Cright%29~~%20%3D%20~~35%5Cleft%28%20%5Ccfrac%7B17x%7D%7B35%7D%2B5%20%5Cright%29%7D%5Cimplies%2018x~~%20%3D%20~~17x%2B175%5Cimplies%20%5Cboxed%7Bx%20%3D175%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7BTom~received%7D%7B17%5Ccdot%20%5Ccfrac%7Bx%7D%7B18%2B17%7D%7D%5Cimplies%20%5Ccfrac%7B17%28175%29%7D%7B35%7D%5Cimplies%20%5Cblacktriangleright%2085%20%5Cblacktriangleleft)
Answer:
10.75
Step-by-step explanation:
To get the average, we always SUM UP all the numbers and divide by the number of numbers.
We do this for "change" row since we want average of "change".
Let's add up all the changes:
11 + 12 + 10 + 10 + 11 + 10 + 11 = 75
How many numbers are there?
There are 7 numbers
Now, the average:
Average = Sum/Number of Numbers
Average = 
The average = 10.75
Instead of brainly you could just open your calculator.
10-3.585 = 6.415