Multiple choice

If the area of a circle is $154 cm^2$, then its perimeter is: $\left[ \pi =\dfrac{22}{7} \right ]$

  1. $22 cm$
  2. $44cm$
  3. $50cm$
  4. $56cm$
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B Correct answer
Explanation

Area = pi * r^2 = 154. (22/7) * r^2 = 154. r^2 = 154 * 7 / 22 = 49. r = 7. Perimeter (circumference) = 2 * pi * r = 2 * (22/7) * 7 = 44.

AI explanation

Use the area of a circle formula, pi times radius squared equals 154. Substituting pi as 22 divided by 7 gives radius squared equals 154 times 7 divided by 22, which simplifies to 49. The radius is 7 cm, so the perimeter, or circumference, formula 2 times pi times radius gives 2 times 22 divided by 7 times 7, resulting in 44 cm.

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