The circumference is given by the formula:
C = 2 pi r
In this case, we are provided with C, but not r, so we must make r the subject
29.5 = 2 x 3.14 x r
Divide by 2 x 3.14 to get r by itself
r = 4.69745.... (don't round off yet!)
Now that we found r, let's use the formula for the area of a circle,
A = pi r^2
= 3.14 x (4.69745...)^2
= 69.3 in^2 (1 dp)
Hope this helped!