If the fabric is 54 inches wide you will need 5 1/4 yards. If it's a printed fabric you will need more.
If you use 60" wide fabric, you'll need approximately 8 yards.
A normal yard is 36 inches. However, a traditional clothyard is 39 inches (extra makes up for the seams) so it would depend on which one is applied in the store or area you buy from/in.
1 yard = 36 inches
There are 36 inches in one yard. Therefore, 30 yards is equal to 30 x 36 = 1080 inches.
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