What is the diameter of a hemisphere with a volume of 458 ft3, to the nearest tenth of
a foot?
Answer Attempt 2 out of 2
ft
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B



Answer :

To find the diameter of a hemisphere with a given volume, we need to first find the radius and then double it to get the diameter. The formula to calculate the volume of a hemisphere is given by: \[ \text{Volume of hemisphere} = \left(\frac{2}{3}\right) \pi r^3 \] Given that the volume of the hemisphere is 458 cubic feet, we can set up the equation and solve for the radius \( r \): \[ 458 = \left(\frac{2}{3}\right) \pi r^3 \] To solve for \( r \), we need to isolate \( r \) on one side of the equation. First, multiply both sides of the equation by the reciprocal of \( \left(\frac{2}{3}\right) \pi \) to get: \[ r^3 = \left(\frac{458}{\left(\frac{2}{3}\right) \pi}\right) \] \[ r^3 = \left(\frac{458 \cdot 3}{2 \pi}\right) \] Now, we'll take the cube root of both sides to find \( r \): \[ r = \left(\frac{458 \cdot 3}{2 \pi}\right)^{1/3} \] Let's compute the right side of the equation step by step: \[ r = \left(\frac{1374}{2 \pi}\right)^{1/3} \] \[ r = \left(\frac{687}{\pi}\right)^{1/3} \] For the purposes of calculation, we will use the approximation \( \pi \approx 3.14159 \). \[ r = \left(\frac{687}{3.14159}\right)^{1/3} \] \[ r \approx (218.60799)^{1/3} \] \[ r \approx 6.024 \] Finally, since the diameter is twice the radius, we have: \[ \text{Diameter} = 2 \cdot r \] \[ \text{Diameter} \approx 2 \cdot 6.024 \] \[ \text{Diameter} \approx 12.048 \] Rounding to the nearest tenth, the diameter of the hemisphere is approximately: \[ \text{Diameter} \approx 12.0 \text{ ft} \] So the diameter of the hemisphere, to the nearest tenth of a foot, is 12.0 feet.