Answer:
The quarter circle's area is 38.47 yard²
Explanation:
The area of a full circle is pi * r ²
The area of a quarter circle is 1/4 * pi * r ²
Given: 
Use 3.14 for pi 
Round to the nearest hundredths. 
Perimeter of quarter circle is 24.99 yards
For r you must leave it as 'r' because we do not know it for now... 
1. Circumference of a full circle = 2* pi * r
2. 1/4 * ( 2 * pi * r )
 1/4 * ( 2 * 3.14 * r )
 1/2 * 3.14 * r
 1.57 * r
3 Since r = 'r' 
We have to 2 sides running from the centre of the 'pie' to the left and right of the quarter circle which both have a length of exactly 'r'. So you just add 2 * r.
4. The outcome of step 2 + step 3 is the perimeter of quarter circle, which was given as 24.99 inch
 1.57 * r + 2 * r = 24.99
( 1.57 + 2 ) * r = 24.99
 3.57 * r = 24.99
Divide left and right of the = sign by 3.57
3.57 / 3.57 * r = 24.99 / 3.57
1 * r = 24.99 / 3.57
 r = 7
The area of a quarter circle is 1/4 * pi * r ²
1/4 * pi * 7²
1/4 * 49 * pi
49/4 * pi
49/4 * 3.14 
38.465
Round to the nearest hundredths gives 38.47 yard²
The quarter circle's area is 38.47 yard²