Amy measurement from her wait st to the finished length of the pant is 35 inches how many inches of fabric does she need
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The answer is 78 inches.
The instructions indicate that you need to purchase fabric that is the length of the pants, and then double it and add an additional 8 inches. Using these instructions, it is calculated by doubling 35 inches, which is 70 inches, and then add 8 inches to it. This gives you an answer of 78 inches.