Answer:
[tex]\huge\underline{\red{A}\blue{n}\pink{s}\purple{w}\orange{e}\green{r} -}[/tex]
the question states that a person named Ben has two copies of the same poster having different sizes , provided they both are squares !
further , we've been given that the side length of the posters are in the ratio of 3:7 and the perimeter of the smaller posted is 27 cm .
We've been asked to find the perimeter of the bigger poster !
so let's start ~
[tex]let\: the \: length \: of \: the \: smaller \: poster \: be \: 3x \\ \\ let \: the \: length \: of \: the \: bigger \: poster \: be \: 7x \\ \\ now \: , \: \\ \\ perimeter \: of \: square = 4 \times side \\ \\ \implies \: perimeter \: of \: shorter \: square = 4 \times 3x \\ \\ \implies \: 27 = 3x \\ \\ x = \cancel\frac{27}{3} \\ \\ \implies\red{\boxed{ \: x = 9 \: cm}}[/tex]
now ,
[tex]side \: length \: of \: bigger \: square = 7x \\ \\ \implies \: 7 \times 9 = 63 \: cm \\ \\ \therefore \: perimeter \: of \: bigger \: square = 4 \times 63 \\ \\ \bold\pink{\implies \: 252 \: cm}[/tex]
hope helpful :D