A square wooden plaque has a square brass inlay in the center, leaving a wooden strip of uniform width around the brass square. If the ratio of the brass area to the wooden area is 25 to 39, which of the following could be the width, in inches, of the wooden strip?
I. 1
II. 3
III. 4
I only
II only
I and II only
I and III only
I, II, and III
假设小正方形面积为X^2,大正方形面积为Y^2
X^2/Y^2-X^2=25/39
则X^2/Y^2=25/64
所以x/y=5/8
wooden strip的宽度是(y-x)/2=3/16y
由于没有说y是整数,所以什么数字都与可能满足条件
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