Multiple choice

If the area of a circle is $38.5{ m }^{ 2 }$, then its circumference will be

  1. $22$
  2. $2.2$
  3. $38.5$
  4. $3.85$
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A Correct answer
Explanation

Area = pi * r^2 = 38.5. Using pi = 22/7, r^2 = 38.5 * 7 / 22 = 12.25, so r = 3.5. Circumference = 2 * pi * r = 2 * (22/7) * 3.5 = 22.

AI explanation

Using the area formula Area = pi x radius^2 and substituting pi as 22/7, we get 38.5 = (22/7) x r^2, which yields r^2 = 12.25 and a radius of 3.5 m. Applying the circumference formula C = 2 x pi x r, we calculate 2 x (22/7) x 3.5 = 44 / 7 x 7 = 22 m. The result is 22.

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