For this case we must find the perimeter of the fence, in a circular way, knowing that the perimeter of a circle is given by:

Where "r" represents the radius of the circle, in this case 
Substituting in the perimeter equation we have:

Rationalizing we have:

Taking out common factor
:

Answer:

Option C
4.75/100= 0.0475 <--- unit rate
0.0475*225= 10.6875
Round to 10.69. <-- cost for 225 pencils
I hope this helps!
~kaikers
This is very confusing!!!!!!!!!1
[4 over x equals 5 over 10]
Solve for x, so you need to isolate/get x by itself in the equation.
Multiply x on both sides

Multiply the inverse of 5/10, which is 10/5, to get rid of the fraction and get x by itself


8 = x
Can I get a picture to help you out