The radius of the two circular fields is in the ratio 3: 7 the area of the first field is what percent less than the area of the second?  Pick.
A) 82.9%	B) 84.2%	C) 81.0%	D) 80.6%	E) 81.6%
r = 3 Ï€r2 = 9   r = 7 Ï€r2 =49   49Ï€ â€“ 40 Ï€   100 ---- ? =&gt; 81.6%.Answer:81.6%
<result>E</result>
The radius of the two circular fields is in the ratio 3: 7 the area of the first field is what percent less than the area of the second?