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Geometry Difficulty 2.8 Junior Find the answer

A square piece of paper, 4 inches on a side, is folded in half vertically. Both layers are then cut in half parallel to the fold. Three new rectangles are formed, a large one and two small ones. What is the ratio of the perimeter of one of the small rectangles to the perimeter of the large rectangle?

Figure (Asymptote source)
draw((0,8)--(0,0)--(4,0)--(4,8)--(0,8)--(3.5,8.5)--(3.5,8)); draw((2,-1)--(2,9),dashed);

Pick one

Solution

The smaller rectangles each have the same height as the original square, but have 14\frac{1}{4} the length, since the paper is folded in half and then cut in half the same way. The larger rectangle has the same height as the original square but has 12\frac{1}{2} the length, since the paper is cut in half after the fold but the fold retains both sides of the larger rectangle. Therefore, the smaller rectangles have dimensions 4×14 \times 1 and the larger rectangle has dimensions 4×24 \times 2. The ratio of their perimeters is 2(4+1)2(4+2)=56,E\frac{2(4+1)}{2(4+2)}=\frac{5}{6}, \boxed{\text{E}}

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.