Ah, that's too many
. To use the area formula, you would need to take the area of your finished hexagon. So, leaving out the seam allowances, measure from one flat side to the opposite flat side (say, the top and bottom) to get your DIAMETER. Now measure the length of one of the six sides to get your SIDE. The AREA = 1.5 x DIAMETER x SIDE.
If you're not a math person, it's easier just to mark off the approximate size on the floor (or fold a sheet to the size you want) and start laying them out
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