SOLUTION: The weight of a synthetic ball varies directly with the cube of its radius. A ball with a rdius of 2 inches weighs 4.40 pounds. Find the weight of a ball with the same material wi

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Question 433404: The weight of a synthetic ball varies directly with the cube of its radius. A ball with a rdius of 2 inches weighs 4.40 pounds. Find the weight of a ball with the same material with a 3 inch radius.

The weight of a ball of the same material with a 3 inch radius is____ lb.

Thanks
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The weight of a synthetic ball varies directly with the cube of its radius.
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w = k*r^3
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Solve for "k" using "A ball with a radius of 2 inches weighs 4.40 pounds".
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4.4 = k*2^3
k = 4.4/8
k = 0.55
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Equation:
w = 0.55*r^3
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Find the weight of a ball with the same material with a 3 inch radius.
w = 0.55*3^3
w = 14.85 lbs
The weight of a ball of the same material with a 3 inch radius is 14.85 lb.
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Cheers,
Stan H.
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