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प्रश्न
The sum of the circumference and diameter of a circle is 176 cm. Find the area of the circle.
उत्तर
Let the radius of a circle = r cm
Circumference of a circle = 2πr cm
Diameter of a circle = 2r cm
Now,
Circumference of a circle + Diameter of a circle = 176cm
⇒ 2πr + 2r = 176
⇒ 2πr(π + 1) = 176
⇒ 2r(3.14 + 1) = 176
⇒ 2r x 4.14 = 176
⇒ r = `(176)/(2 xx 4.14)`
= 21.26cm
∴ Area of a circle
= πr2
=3.14 x 21.26 x 21.26
= 1419.24cm2.
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