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A cone of height 24 cm and radius of bas...

A cone of height 24 cm and radius of base 6 cm is made up of modeling clay, A child reshapes it in the form of a sphere. Find the radius of the sphere and hence find the surface area of this sphere.

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To solve the problem step by step, we will follow these steps: ### Step 1: Calculate the Volume of the Cone The formula for the volume of a cone is given by: \[ V_{\text{cone}} = \frac{1}{3} \pi r^2 h \] where \( r \) is the radius of the base and \( h \) is the height. Given: - Height \( h = 24 \) cm - Radius \( r = 6 \) cm Substituting the values into the formula: \[ V_{\text{cone}} = \frac{1}{3} \pi (6)^2 (24) \] Calculating \( (6)^2 = 36 \): \[ V_{\text{cone}} = \frac{1}{3} \pi (36)(24) \] Calculating \( 36 \times 24 = 864 \): \[ V_{\text{cone}} = \frac{1}{3} \pi (864) \] Calculating \( \frac{864}{3} = 288 \): \[ V_{\text{cone}} = 288 \pi \text{ cm}^3 \] ### Step 2: Set the Volume of the Sphere Equal to the Volume of the Cone The volume of the sphere is given by: \[ V_{\text{sphere}} = \frac{4}{3} \pi r^3 \] Since the cone is reshaped into a sphere, we have: \[ V_{\text{cone}} = V_{\text{sphere}} \] Thus, \[ 288 \pi = \frac{4}{3} \pi r^3 \] ### Step 3: Cancel \(\pi\) from Both Sides Dividing both sides by \(\pi\): \[ 288 = \frac{4}{3} r^3 \] ### Step 4: Solve for \( r^3 \) To isolate \( r^3 \), multiply both sides by \( \frac{3}{4} \): \[ r^3 = 288 \times \frac{3}{4} \] Calculating \( 288 \times \frac{3}{4} = 216 \): \[ r^3 = 216 \] ### Step 5: Find the Radius of the Sphere Taking the cube root of both sides: \[ r = \sqrt[3]{216} \] Calculating the cube root: \[ r = 6 \text{ cm} \] ### Step 6: Calculate the Surface Area of the Sphere The formula for the surface area of a sphere is: \[ A = 4 \pi r^2 \] Substituting the radius \( r = 6 \) cm: \[ A = 4 \pi (6)^2 \] Calculating \( (6)^2 = 36 \): \[ A = 4 \pi (36) \] Calculating \( 4 \times 36 = 144 \): \[ A = 144 \pi \text{ cm}^2 \] ### Final Answer The radius of the sphere is \( 6 \) cm and the surface area of the sphere is \( 144 \pi \text{ cm}^2 \). ---
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