The scale of two similar quadrilaterals is 1: 4. the perimeter of the smaller quadrilateral is 80 centimeters. what is the perimeter of the largest quadrilateral?

Set it up as a ratio, with the information for the smaller on top and the info for the larger on bottom.  1/4 = 80/x.  Since perimeter is a one-to-one relationship, it's not squared or cubed like area or volume would be.  Cross multiply to get that x = 320