Answer: 11/20
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Work Shown:
x = unknown horizontal length
1/5 = 0.2
Perimeter = 2*(width + length)
P = 2*(0.2 + x)
P = 0.4 + 2x
Set this equal to the given perimeter of 1 & 1/2 = 1.5 and solve for x
0.4 + 2x = 1.5
2x = 1.5-0.4
2x = 1.1
x = (1.1)/2
x = 0.55
x = 55/100
x = (5*11)/(5*20)
x = 11/20
