I don't understand how to find the aproximate area of a shaded region
This problem has a big cirlce with 1/4 shadded with a radius of 20 cm.
the answer chocies are
A. 90 cm squared
B. 270 cm squared
C. 314 cm squared
D. 1.256 cm squared
how do I find the answer?
pi*r^2
3.14*20cm.^2
=1256.63
take that and divide by four and you get 314.16
I don't understand how you got 1256.63
I don't either I got 62.8
To find the approximate area of the shaded region, you need to subtract the area of the unshaded part (which is a quarter of a circle) from the area of the entire circle.
Start by finding the area of the entire circle using the formula: A = πr², where A is the area and r is the radius. In this case, the radius is given as 20 cm, so the area of the entire circle is:
A_circle = π(20 cm)²
Now, to find the area of the shaded region, you need to subtract the area of the unshaded part. Since the unshaded part is a quarter of the circle, you can calculate its area by dividing the area of the entire circle by 4:
A_unshaded = A_circle / 4
After finding the area of the unshaded part, subtract it from the area of the entire circle to get the approximate area of the shaded region:
A_shaded = A_circle - A_unshaded
Once you have the value of A_shaded, compare it to the answer choices given to determine the correct option.