Explanation:
We can find the perimeter of a rectangle by adding together the length and width and then multiplying that sum by 2.
The width is 4/5 * 3 1/4 = 4/5 * 13/4 = 13/5 = 2 3/5.
3 1/4 + 2 3/5 = 3 5/20 + 2 12/20 = 5 17/20
5 17/20 * 2 = 117/20 * 2 = 117/10 = 11 7/10 in.