SOLUTION: If a 10-inch fish weighs 3 pounds, how much does a 15-inch fish weigh assuming the two fish are proportional? The answer is 10.125 pounds but I'm not sure how to get this.

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Question 926639: If a 10-inch fish weighs 3 pounds, how much does a 15-inch fish weigh assuming the two fish are proportional? The answer is 10.125 pounds but I'm not sure how to get this.
Found 2 solutions by Alan3354, stanbon:
Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website!
If a 10-inch fish weighs 3 pounds, how much does a 15-inch fish weigh assuming the two fish are proportional? The answer is 10.125 pounds but I'm not sure how to get this.
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Volume of a solid is proportional to the cube of its dimensions.
2x the radius ---> 8x the volume, etc.
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A 15 inch fish is 1.5 x the length of a 10 inch fish.
1.5^3 = 3.375
3*3.375 = 10.125 pounds

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
If a 10-inch fish weighs 3 pounds, how much does a 15-inch fish weigh assuming the two fish are proportional? The answer is 10.125 pounds but I'm not sure how to get this.
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wt/length = wt/length
x/15 = 3/10
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x = 15*3/10
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x = 45/10
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x = 4.5 lbs
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Can't imagine where your 10.125 came from.
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Cheers,
Stan H.
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