Answer:
P = length + width x 2P = 3.5ft + 5.5ft x 2P = 9ft x 2P = 18ft + 1.5ft (the new mural)P = 19.5ft
Therefore the perimeter of Rosalie's new mural is 19.5ft
Ratio of sweaters to dresses = 8 : 5
Sum of ratios = 13
Let number of sweater + dresses = x
8 subtracted from the product of 9 and x
Hope this helps!