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The area enclosed between two concentric circles ofradii 5 cm and 10 cm is the same as between the thirdand the second concentric circle. Find the total area ofthe third circle. |
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Answer» Answer: total AREA of the 3rd ring = area of 1ST ring + area between 1st and 2nd ring + area between 2nd and 3rd ring area of 1st ring = π(R1)² => π(5²) => 25π ..........1 area between the 1st and 2nd ring => => π [ (r2)² - (r1)² ] => π (10² - 5²) => π ( 100 - 25) => 75π .................2 area between 2nd and 3rd ring is same as area between 1st and 2nd ring = 75π ..........3 therefore total area of 3rd circle = 1+2+3 => 25π + 75π + 75π => 175π => 175 × 22/7 => 550 cm² |
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