To calculate the area of a circle given the diameter of 18 inches, we first need to find the radius. The radius is half of the diameter.
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Calculate the radius: \[ r = \frac{d}{2} = \frac{18}{2} = 9 \text{ inches} \]
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Use the area formula for a circle: \[ A = \pi r^2 \quad (\text{where } \pi \approx 3.14) \]
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Substitute the radius into the formula: \[ A = 3.14 \times (9)^2 \] \[ A = 3.14 \times 81 \] \[ A = 254.34 \text{ in}^2 \]
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Round to the nearest hundredth: \[ A \approx 254.34 \text{ in}^2 \]
Thus, the area of the circle is 254.34 in².