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The radius of a cylindrical roller is 14...

The radius of a cylindrical roller is 140 cm and its length is 100 cm. It takes 500 complete revolutions to level a playground completely. Find the area of playground in `m^(2)`.

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To solve the problem step by step, we will follow the outlined procedure to find the area of the playground leveled by the cylindrical roller. ### Step 1: Identify the given values - Radius of the cylindrical roller (r) = 140 cm - Length of the cylindrical roller (h) = 100 cm - Number of revolutions = 500 ### Step 2: Calculate the curved surface area (CSA) of the cylindrical roller The formula for the curved surface area of a cylinder is: \[ \text{CSA} = 2 \pi r h \] Substituting the values: \[ \text{CSA} = 2 \times \frac{22}{7} \times 140 \times 100 \] ### Step 3: Simplify the calculation 1. Calculate \(2 \times \frac{22}{7} = \frac{44}{7}\). 2. Now, multiply by the radius and height: \[ \text{CSA} = \frac{44}{7} \times 140 \times 100 \] 3. First, calculate \(140 \times 100 = 14000\). 4. Now, calculate: \[ \text{CSA} = \frac{44 \times 14000}{7} \] 5. Calculate \(44 \times 2000 = 88000\). 6. Finally, divide by 7: \[ \text{CSA} = 88000 \text{ cm}^2 \] ### Step 4: Calculate the total area covered in 500 revolutions The area covered in 500 revolutions is: \[ \text{Total Area} = \text{CSA} \times \text{Number of Revolutions} \] \[ \text{Total Area} = 88000 \times 500 \] Calculating this gives: \[ \text{Total Area} = 44000000 \text{ cm}^2 \] ### Step 5: Convert the area from square centimeters to square meters To convert from square centimeters to square meters, we use the conversion factor: \[ 1 \text{ m}^2 = 10000 \text{ cm}^2 \] Thus, we convert: \[ \text{Area in m}^2 = \frac{44000000 \text{ cm}^2}{10000} \] Calculating this gives: \[ \text{Area in m}^2 = 4400 \text{ m}^2 \] ### Final Answer The area of the playground is: \[ \boxed{4400 \text{ m}^2} \]
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NAVNEET PUBLICATION - MAHARASHTRA BOARD-SURFACE AREAS AND VOLUMES-SKILL TESTING EXERCISE
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