Step-by-step explanation:
Given that,
The height of the cone, h = 24 cm
The radius of the cone, r = 10 cm
The slant height of the cone is :
![l=\sqrt{h^2+r^2} \\\\l=\sqrt{24^2+10^2} \\\\l=26\ cm](https://tex.z-dn.net/?f=l%3D%5Csqrt%7Bh%5E2%2Br%5E2%7D%20%5C%5C%5C%5Cl%3D%5Csqrt%7B24%5E2%2B10%5E2%7D%20%5C%5C%5C%5Cl%3D26%5C%20cm)
The lateral area of the cone is given by :
![A=\pi rl\\\\=3.14\times 10\times 26\\\\=816.4\ cm^2\approx 816\ cm^2](https://tex.z-dn.net/?f=A%3D%5Cpi%20rl%5C%5C%5C%5C%3D3.14%5Ctimes%2010%5Ctimes%2026%5C%5C%5C%5C%3D816.4%5C%20cm%5E2%5Capprox%20816%5C%20cm%5E2)
The surface area of the cone is given by :
![A=2\pi rh\\\\=2\times 3.14\times 10\times 24\\\\=1507.2 \approx 1507\ cm^2](https://tex.z-dn.net/?f=A%3D2%5Cpi%20rh%5C%5C%5C%5C%3D2%5Ctimes%203.14%5Ctimes%2010%5Ctimes%2024%5C%5C%5C%5C%3D1507.2%20%5Capprox%201507%5C%20cm%5E2)
Answer:
$8.44
Step-by-step explanation:
To find the 20%
x/14.45=20/100
14.45×20=289
289÷100=2.89
We then subtract 2.89 from 14.45 to get the selling price.
14.45-2.89=11.56
$11.56 is the price of the baseball hat on sale.
To get the change
20-11.56=8.44
$8.44 is the change
<u><em>I</em><em> </em><em>hope</em><em> </em><em>this</em><em> </em><em>helped</em><em>!</em><em> </em><em>:</em><em>)</em></u>
Answer:
a) h = 123/x^2
b) S = x^2 +492/x
c) x ≈ 6.27
d) S'' = 6; area is a minimum (Y)
e) Amin ≈ 117.78 m²
Step-by-step explanation:
a) The volume is given by ...
V = Bh
where B is the area of the base, x^2, and h is the height. Filling in the given volume, and solving for the height, we get:
123 = x^2·h
h = 123/x^2
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b) The surface area is the sum of the area of the base (x^2) and the lateral area, which is the product of the height and the perimeter of the base.
![S=x^2+Ph=x^2+(4x)\dfrac{123}{x^2}\\\\S=x^2+\dfrac{492}{x}](https://tex.z-dn.net/?f=S%3Dx%5E2%2BPh%3Dx%5E2%2B%284x%29%5Cdfrac%7B123%7D%7Bx%5E2%7D%5C%5C%5C%5CS%3Dx%5E2%2B%5Cdfrac%7B492%7D%7Bx%7D)
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c) The derivative of the area with respect to x is ...
![S'=2x-\dfrac{492}{x^2}](https://tex.z-dn.net/?f=S%27%3D2x-%5Cdfrac%7B492%7D%7Bx%5E2%7D)
When this is zero, area is at an extreme.
![0=2x -\dfrac{492}{x^2}\\\\0=x^3-246\\\\x=\sqrt[3]{246}\approx 6.26583](https://tex.z-dn.net/?f=0%3D2x%20-%5Cdfrac%7B492%7D%7Bx%5E2%7D%5C%5C%5C%5C0%3Dx%5E3-246%5C%5C%5C%5Cx%3D%5Csqrt%5B3%5D%7B246%7D%5Capprox%206.26583)
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d) The second derivative is ...
![S''=2+\dfrac{2\cdot 492}{x^3}=2+\dfrac{2\cdot 492}{246}=6](https://tex.z-dn.net/?f=S%27%27%3D2%2B%5Cdfrac%7B2%5Ccdot%20492%7D%7Bx%5E3%7D%3D2%2B%5Cdfrac%7B2%5Ccdot%20492%7D%7B246%7D%3D6)
This is positive, so the value of x found represents a minimum of the area function.
__
e) The minimum area is ...
![S=x^2+\dfrac{2\cdot 246}{x}=(246^{\frac{1}{3}})^2+2\dfrac{246}{246^{\frac{1}{3}}}=3\cdot 246^{\frac{2}{3}}\approx 117.78](https://tex.z-dn.net/?f=S%3Dx%5E2%2B%5Cdfrac%7B2%5Ccdot%20246%7D%7Bx%7D%3D%28246%5E%7B%5Cfrac%7B1%7D%7B3%7D%7D%29%5E2%2B2%5Cdfrac%7B246%7D%7B246%5E%7B%5Cfrac%7B1%7D%7B3%7D%7D%7D%3D3%5Ccdot%20246%5E%7B%5Cfrac%7B2%7D%7B3%7D%7D%5Capprox%20117.78)
The minimum area of metal used is about 117.78 m².
Answer:
<h3>6 days</h3>
Step-by-step explanation:
Given the inequality expression of the total cost (c) in dollars of renting a car for n days as c ≥ 125 + 50n
To get the maximum number of days for which a car could be rented if the total cost was $425, substitute c = 425 into the expression and find n
425 ≥ 125 + 50n
Subtract 125 from both sides
425 - 125 ≥ 125 + 50n - 125
300≥ 50n
Divide both sides by 50
300/50≥50n/50
6 ≥n
Rearrange
n≤6
<em>Hence the maximum number of days for which a car could be rented if the total cost was $425 is 6days</em>
<em></em>
Answer:
Think its B. but if not it should be E.
Step-by-step explanation: