The independent variable is time and dependent is distance.
Daniela made her error on step 3 because it says: <span>
<span>"Find the ratio of the differences of the means compared to the mean absolute deviation.
</span><span>
She didn't find the difference between the today and last week means. She just put the mean as a whole.</span></span>
![\bf \textit{volume of a cone}\\\\ V=\cfrac{\pi r^2 h}{3}~~ \begin{cases} r=radius\\ h=height\\[-0.5em] \hrulefill\\ r=23.9\\ h=100 \end{cases}\implies V=\cfrac{\pi (23.9)^2(100)}{3} \\\\\\ V=\cfrac{57121\pi }{3}\implies V\approx 59816.97\implies \stackrel{\textit{rounded up}}{V=59817} \\\\[-0.35em] ~\dotfill](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Bvolume%20of%20a%20cone%7D%5C%5C%5C%5C%20V%3D%5Ccfrac%7B%5Cpi%20r%5E2%20h%7D%7B3%7D~~%20%5Cbegin%7Bcases%7D%20r%3Dradius%5C%5C%20h%3Dheight%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20r%3D23.9%5C%5C%20h%3D100%20%5Cend%7Bcases%7D%5Cimplies%20V%3D%5Ccfrac%7B%5Cpi%20%2823.9%29%5E2%28100%29%7D%7B3%7D%20%5C%5C%5C%5C%5C%5C%20V%3D%5Ccfrac%7B57121%5Cpi%20%7D%7B3%7D%5Cimplies%20V%5Capprox%2059816.97%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Brounded%20up%7D%7D%7BV%3D59817%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill)
now, for the second one, we know the diameter is 10, thus its radius is half that or 5.
![\bf \textit{volume of a cone}\\\\ V=\cfrac{\pi r^2 h}{3}~~ \begin{cases} r=radius\\ h=height\\[-0.5em] \hrulefill\\ r=5\\ V=225 \end{cases}\implies 225=\cfrac{\pi (5)^2 h}{3}\implies 225=\cfrac{25\pi h}{3} \\\\\\ \cfrac{225}{25\pi }=\cfrac{h}{3}\implies \cfrac{9}{\pi }=\cfrac{h}{3}\implies \cfrac{27}{\pi }=h\implies 8.59\approx h\implies \stackrel{\textit{rounded up}}{8.6=h}](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Bvolume%20of%20a%20cone%7D%5C%5C%5C%5C%20V%3D%5Ccfrac%7B%5Cpi%20r%5E2%20h%7D%7B3%7D~~%20%5Cbegin%7Bcases%7D%20r%3Dradius%5C%5C%20h%3Dheight%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20r%3D5%5C%5C%20V%3D225%20%5Cend%7Bcases%7D%5Cimplies%20225%3D%5Ccfrac%7B%5Cpi%20%285%29%5E2%20h%7D%7B3%7D%5Cimplies%20225%3D%5Ccfrac%7B25%5Cpi%20h%7D%7B3%7D%20%5C%5C%5C%5C%5C%5C%20%5Ccfrac%7B225%7D%7B25%5Cpi%20%7D%3D%5Ccfrac%7Bh%7D%7B3%7D%5Cimplies%20%5Ccfrac%7B9%7D%7B%5Cpi%20%7D%3D%5Ccfrac%7Bh%7D%7B3%7D%5Cimplies%20%5Ccfrac%7B27%7D%7B%5Cpi%20%7D%3Dh%5Cimplies%208.59%5Capprox%20h%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Brounded%20up%7D%7D%7B8.6%3Dh%7D)
The present dimensions are : length = 12 feet
width = 9 feet
Area = 12* 9 = 108 feet squared
If the dimensions are increased by x feet the dimensions are :
length = 12 + x
width = 9+ x
Area = ( 12+x)( 9+x)
new area = initial area * 2
( 12+ x)( 9+ x) = 2 * 108
12*9 + 12x + 9x + xx = 216
108 + 21 x + x^2 = 216
x^2+ 21x = 216-108
x^2 + 21x = 108
x^2 + 21x -108 = 0
let us plug a= 1 b= 21 c= -108 in quadratic formula
x= [-21 + / - ( 21^2 - 4* 1 * -108 )^(1/2 ]/ 2* 1
x= 4.27
Answer :
Both sides are increased by 4.27 feet .
No. Because no can be -1, either the solution is positive or the person wasn't born.
