#### Answer

width of the frame =2 inch

#### Work Step by Step

Since we are given that perimeter = 72 inch
Formula to calculate the perimeter of a painting with frame is :
Perimeter= 2( Length + Width) or, $P= 2(l+w)$
Thus, $72= 2 (12+2x+16+2x)$
or, $72=2(28+4x)$
or, $72=56+8x$
Thus, $x=2$ inch
Hence, width of the frame =2 inch