math
posted by scott .
Rectangle ABCD is 12 inches long and has a perimeter of 54 inches. Rectangle LMNO is similar to rectangle ABCD and is 2.4 feet long. What is the width of the rectangle LMNO?

Perimeter ABCD = 54
L = 12 in
Perimeter LMNO = x
L = 2.4 ft = 28.8 in
P = 2w + 2L
Use Ratio to find x (perimeter LMNO)
12/28.8 = 54/x
Cross multiply
12x = 1555.2
x = 129.6
LMNO P = 129.6
L = 28.8
P = 2w + 2L
129.6 = 2w + 2(28.8)
Solve for w, width of LMNO