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Taking pi=3.14 , find the radius and cir...

Taking `pi=3.14` , find the radius and circumference of a circle whose area is :
(i) `200.96cm^(2)`
(ii) `379.94 m^(2)`

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The correct Answer is:
Let's solve the problem step by step. ### Part (i): Area = 200.96 cm² 1. **Write the formula for the area of a circle**: \[ \text{Area} = \pi r^2 \] 2. **Substitute the given values**: \[ 200.96 = 3.14 \times r^2 \] 3. **Rearrange the equation to solve for \( r^2 \)**: \[ r^2 = \frac{200.96}{3.14} \] 4. **Calculate \( r^2 \)**: \[ r^2 = \frac{200.96}{3.14} = 64 \] 5. **Find the radius \( r \)**: \[ r = \sqrt{64} = 8 \text{ cm} \] 6. **Calculate the circumference**: \[ \text{Circumference} = 2 \pi r = 2 \times 3.14 \times 8 \] 7. **Perform the multiplication**: \[ \text{Circumference} = 2 \times 3.14 \times 8 = 50.24 \text{ cm} \] ### Summary for Part (i): - Radius = 8 cm - Circumference = 50.24 cm --- ### Part (ii): Area = 379.94 m² 1. **Write the formula for the area of a circle**: \[ \text{Area} = \pi r^2 \] 2. **Substitute the given values**: \[ 379.94 = 3.14 \times r^2 \] 3. **Rearrange the equation to solve for \( r^2 \)**: \[ r^2 = \frac{379.94}{3.14} \] 4. **Calculate \( r^2 \)**: \[ r^2 = \frac{379.94}{3.14} = 121 \] 5. **Find the radius \( r \)**: \[ r = \sqrt{121} = 11 \text{ m} \] 6. **Calculate the circumference**: \[ \text{Circumference} = 2 \pi r = 2 \times 3.14 \times 11 \] 7. **Perform the multiplication**: \[ \text{Circumference} = 2 \times 3.14 \times 11 = 69.08 \text{ m} \] ### Summary for Part (ii): - Radius = 11 m - Circumference = 69.08 m ---
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