Measuring a pig with a tape measure results in a pretty accurate body weight (within 3%) if you don't own a set of scales. This technique is taken from the Old Farmer's Almanac 1993. I have used this technique several times with very good results:
Using a flexible tape measure, like those found in the sewing section of any grocery or department store, take two measurements of your pig:
1) Measure the girth (G). Your tape measure needs to go around the body just behind the front legs and over the shoulder area.
Square this result (multiply this measurement by itself).
2) Measure the length (L) of your pig. Start at the top of the head between the ears and measure down to the start, or base, of the tail (not the end of the tail).
3) Take the result you obtained in Step 1 and multiply it by the length of your pig (Step 2).
4) Calculate the weight (W) by dividing the number you get in Step 3 by 400.
For you math-types: W=[(GxG) x L]/400
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