MHB Find the area of sector in a circle in terms of pi. (Geometry)

AI Thread Summary
To find the area of a sector in a circle, the formula involves multiplying the fraction of the circle represented by the angle by the area of the entire circle. In this case, the angle of 270 degrees simplifies to 3/4 when divided by 360 degrees. The area \(A\) is calculated as \(A = \frac{3}{4}\pi r^2\). With a radius of 12 meters, substituting into the formula gives an area of 108π. The final answer of 108π is confirmed as correct.
Etrujillo
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So far i have 270/360× (pi)r^ i don't know what to do next please help.
 

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I would first reduce:

$$\frac{270^{\circ}}{360^{\circ}}=\frac{3}{4}$$

And so we now have the area \(A\):

$$A=\frac{3}{4}\pi r^2$$

Can you identify the radius \(r\) of the circle from the diagram?
 
The radius i believe is 12m so when i plug in your formula i get 108pi as the answer. Am i correct?
 
Yes, 108\pi is correct.
 

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