Consider two rectangular sheets, Sheet M and Sheet N of dimensions $6 \mathrm{cm} \times 4 \mathrm{cm}$ each. Folding operation 1: The sheet is folded into half by joining the short edges of the current shape. Folding operation 2: The sheet is folded into half by joining the long edge of the current shape. Folding operation 1 is carried out on sheet M three times. Folding operation 2 is carried out on sheet N three times. The ratio of perimeters of the final folded shape of sheet N to the final folded shape of sheet M is ____ .
(a)3 : 2
(b)5 : 13
(c)$7: 5$
(d)$13: 7$
Answer
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