The radius of a circular field, whose area is equal to the sum of the area of…

2024

The radius of a circular field, whose area is equal to the sum of the area of the three circular fields having radii 8 m, 9 m and 12 m respectively, is equal to :

  1. A.

    16 m / 16 मी०

  2. B.

    17 m / 17 मी०

  3. C.

    18 m / 18 मी०

  4. D.

    19 m / 19 मी०

Attempted by 152 students.

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Correct answer: B

Step 1: Calculate the area of each circle using the formula A = πr².

Area of first circle = π × 8² = 64π m²

Area of second circle = π × 9² = 81π m²

Area of third circle = π × 12² = 144π m²

Step 2: Sum the areas: Total area = 64π + 81π + 144π = 289π m²

Step 3: Let the radius of the required circle be R. Area = πR² = 289π

Step 4: Solve for R: R² = 289 R = √289 = 17 m

हिन्दी उत्तर:

चरण 1: प्रत्येक वृत्त का क्षेत्रफल πr² के सूत्र से ज्ञात करें।

पहले वृत्त का क्षेत्रफल = π × 8² = 64π मी०²

दूसरे वृत्त का क्षेत्रफल = π × 9² = 81π मी०²

तीसरे वृत्त का क्षेत्रफल = π × 12² = 144π मी०²

चरण 2: क्षेत्रफलों का योग करें: कुल क्षेत्रफल = 64π + 81π + 144π = 289π मी०²

चरण 3: माना आवश्यक वृत्त की त्रिज्या R है। क्षेत्रफल = πR² = 289π

चरण 4: R के लिए हल करें: R² = 289 R = √289 = 17 मी०

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