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The volume of the cone is 462 yd.³ The height is 3ft. What is the radius of the cone? use 22/7 for pie

User Syntonym
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1 Answer

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We are asked to determine the radius of a cone given its volume and its height. To do that we will use the following formula for the volume of a cone:


V=(\pi r^2h)/(3)

Now, we solve for the radius "r". First, we multiply both sides by 3:


3V=\pi r^2h

Now, we divide both sides by pi and the height:


(3V)/(\pi h)=r^2

Now, we take the square root to both sides:


\sqrt{(3V)/(\pi h)}=r

Now, we convert the height from feet to yards using the following conversion factor:


1\text{ yd}=\text{ 3ft}

Multiplying by the conversion factor we get that the height is 1 yd:

Now, we substitute the values:


\sqrt{(3(462yd^3))/(((22)/(7))(1yd))}=r

Solving the operations:


21yd=r

Therefore, the radius is 21 yd.

User Khiet
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