The formula for the volume of a cone is ...
... V = (1/3)πr²h = (1/3)π(d/2)²h = (π/12)d²h
for height h and diameter d.
Then the volume of the cone is ...
... V = (π/12)·(2 in)²·(4 in) = 4π/3 in³ ≈ 4.189 in³
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The formula for the volume of a cylinder is ...
... V = πr²h = π(d/2)²h = (π/4)d²h
Then the volume of the cylinder is ...
... V = (π/4)·(2 in)²·(6 in) = 6π in³ ≈ 18.850 in³
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The difference in volume is ...
... 18.850 in³ - 4.189 in³ = 14.661 in³ ≈ 14.7 in³
