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The total surface area of a solid cylin...

The total surface area of a solid cylinder is `616 cm^(2)`. If the ratio between its curved surface area and total surface area is 1:2, find the volume of the cylinder.

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To find the volume of the cylinder given the total surface area and the ratio of the curved surface area to the total surface area, follow these steps: ### Step 1: Understand the given information - Total Surface Area (TSA) of the cylinder = 616 cm² - Ratio of Curved Surface Area (CSA) to Total Surface Area = 1:2 ### Step 2: Write the formulas - The formula for the Total Surface Area (TSA) of a cylinder is: \[ \text{TSA} = 2\pi r (r + h) \] - The formula for the Curved Surface Area (CSA) of a cylinder is: \[ \text{CSA} = 2\pi rh \] ### Step 3: Set up the ratio From the given ratio of CSA to TSA: \[ \frac{\text{CSA}}{\text{TSA}} = \frac{1}{2} \] Substituting the formulas: \[ \frac{2\pi rh}{2\pi r(r + h)} = \frac{1}{2} \] This simplifies to: \[ \frac{h}{r + h} = \frac{1}{2} \] ### Step 4: Cross-multiply to solve for h Cross-multiplying gives: \[ 2h = r + h \] Rearranging the equation: \[ 2h - h = r \implies h = r \] ### Step 5: Substitute h in the TSA formula Since \( h = r \), we can substitute \( h \) in the TSA formula: \[ \text{TSA} = 2\pi r (r + r) = 2\pi r (2r) = 4\pi r^2 \] Setting this equal to the given TSA: \[ 4\pi r^2 = 616 \] ### Step 6: Solve for r Rearranging gives: \[ \pi r^2 = \frac{616}{4} = 154 \] Substituting \( \pi \) as \( \frac{22}{7} \): \[ \frac{22}{7} r^2 = 154 \] Multiplying both sides by 7: \[ 22r^2 = 154 \times 7 \] Calculating \( 154 \times 7 \): \[ 154 \times 7 = 1078 \] So: \[ 22r^2 = 1078 \] Dividing both sides by 22: \[ r^2 = \frac{1078}{22} = 49 \] Taking the square root: \[ r = 7 \text{ cm} \] ### Step 7: Find h Since \( h = r \): \[ h = 7 \text{ cm} \] ### Step 8: Calculate the volume of the cylinder The volume \( V \) of a cylinder is given by: \[ V = \pi r^2 h \] Substituting the values: \[ V = \frac{22}{7} \times 7^2 \times 7 \] Calculating: \[ V = \frac{22}{7} \times 49 \times 7 = 22 \times 49 = 1078 \text{ cm}^3 \] ### Final Answer The volume of the cylinder is \( 1078 \text{ cm}^3 \). ---
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