What is the radius of a circular field whose area is equal to the sum of the areas of three smaller circular fields of radii 8 m, 9 m and 12 m, respectively?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 17 m.
Area of circle = πr2
Where, r = radius of circle
Let the radius of the bigger circle be R.
According to the question;
⇒ πR2 = π × 82 + π × 92 + π × 122
⇒ R2 = 64 + 81 + 144
⇒ R2 = 289
⇒ R = 17 m