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The volume of a cone is 251.2 cubic inches. The height of the cone is 15 inches. What is the radius of the cone, rounded to the nearest inch? Use π = 3.14.

16 inches
8 inches
6 inches
4 inches

User Mkj
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2 Answers

4 votes
4 votes

Answer: [D]: 4 inches .

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Explanation:

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Formula for Volume of a cone:

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V = r² *h * (1/3) ;

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Given: V = 251.2 in³ ;

h = 15 in.

π = 3.14 ;

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Plug in our given values to find, "r" :

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251.2 in³ = (3.14) * r² * (15 in.) * (1/3) ;

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251.2 in³ = (15.7 in.) * r²

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Divide each side of the equation by: "(15.7 in.)" ;

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251.2 in³ / (15.7 in.) = (15.7 in.) * r² / (15.7 in.) ;

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r² = 16

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Now, take the positive "square root" of EACH SIDE of the equation;

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to isolate "r" on one side of the equation ; and to solve for "r" ;

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√(r²) = √(16 in²) ;

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r = 4 inches; which is Answer choice: [D] .

Explanation:

User Symi
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Answer:

I hope this helps you!

6 inches

Help ASAP The volume of a cone is 251.2 cubic inches. The height of the cone is 15 inches-example-1
User John Allers
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