One pair of corresponding sides of two similar polygons measures 12 and 15. The perimeter of the smaller polygon is 30. Find the perimeter of the larger.

The perimeter of the larger polygon will have the same ratio to the perimeter of the smaller as the ratio of the corresponding sides. Therefore, the larger polygon will have a perimeter of 30 (15/12) = 37.5, or 38 to the justified number of significant digits stated.