The ratio of the area (in cm^{2}) to the circumference (in cm) of a circle is 21 ∶ 2. Find the area of the circle.

- 154 cm
^{2} - 616 cm
^{2} - 346.5 cm
^{2} - 1386 cm
^{2}

Option 4 : 1386 cm^{2}

Given:

Area : Circumference = 21 ∶ 2

Formula Used:

Area of circle = πr2

The circumference of circle = 2πr

Where,

r = radius of the circle

Calculation:

Let the radius of the circle be ‘r’ cm

According to the question, we have

(πr2/2πr) = 21/2

⇒ r/2 = 21/2

⇒ r = 21 cm

Now,

The area of circle = (22/7) × 21 × 21

⇒ 1386 cm^{2}

**∴ The area of the circle is 1386 cm ^{2}**.

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