Question

The figure shows two regular pentagons. What is the perimeter of the larger pentagon?

A. 5n

B. 10n

C. 15n

D. 60n

Answer 1

As shown in picture,

perimeter of inside pentagon: p1 = n + n + n + n + n = 5n

ratio between inside pentagon and outside pentagon: r = 6/(6 + 6) = 1/2

=> perimeter of outside pentagon: p2 = 2 x p1 = 2 x 5n = 10n

=> Option B is correct

Hope this helps!

:)