Farmers' short rules of arithmetic
1. How to find the number of Tons of Hay in a Mow. - Multiply the length
of the mow in feet, by the width in feet, and that by the height in feet and
divide the result by 400 if the hay is well settled (or by 500 for new hay)
and you have the number of tons in the mow.

2. How to find the number of tons of hay in a stack. Let the hay settle 30
days. Then measure over the stack with a tape line from ground to ground in
feet and then find the width of the stack in feet and add the two results> together and divide the sum by 4, then multiply this result by itself, and> multiply that number by the length of he stack in feet, and divide the product> by 400(or for greater accuracy, by 420) and you will have the number of tons
in the hay stack.

3. How to measure Ear Corn in a Crib - Multiply the length in feet by the height in feet, and that again by the width in feet, and multiply the result by 4, (or for good, sound corn well settled, by 5) and cut off the right hand figure, and you have the contents in bushels of shelled corn. When the crib is flared at the side, find the average width by adding together the top and bottom widths and dividing by 2.

4. How to Find the Number of Bushels of Grain in a Box or Bin - Multiply the length in feet by the height in feet, and that again by the breadth in feet and then again by 8, and cut off the right hand figure. The result will be the number of bushels.

6. How to Find the Number of Heaped Bushels of Ear Corn, Apples or Potatoes in a Crib - Multiply the length in feet by the breadth in feet, and that again by the height in feet and multiply the result by 6, cut off the right hand figure and you have the number of heaped bushels.

7. How to Find the Contents of a Wagon Box - Multiply the depth of the wagon box in inches by 2, and you have the number of bushels. A common wage box is a little more than ten feet long and three feet wide and will hold about two bushels for every inch in depth. If the wagon box is 11 feet long, multiply the depth in inches by 2 and add one-tenth of the number of bushels to itself.

8. How to Find the Weight of Cattle by Measurement - Multiply the distance
around the animal (back of the fore-shoulder) in feet by itself, and then multiply that result by 17.5 and you have the weight of the animal very near. For more accurate results instead of multiplying by 17.5 multiply by 5 times the length of the animal in feet (measuring from the fore-part of the should blade to the bone at the tail, in a vertical line with the buttocks) and divide this product by 1.5 for average cattle, (very fat by 1.425; very lean by 1.575) and you have the dressed weight of the animal.

9. How to Find the Price per Hundred when sold by the Ton. - If the cistern or tank is square, multiply the height width and depth in feet together and divide the product by 4, and the result will equal the number of barrels the cistern will hold. If the cistern or tank is round, multiply the diameter in feet by itself and multiply that by the depth in feet, and divide the product by 5 and you will have the number of barrels the cistern or tank will hold.

10. How to Find the Contents of Barrels and Casks - Add together the diameters at the bung and head in inches and divide the sum by 2, and the result will be the average diameter. Now multiply this result by itself, and multiply the product by the length of the barrel or cash, in inches. Multiply this result again by 34, and cut off the four right hand figures and you will have the number of gallons.

11. Gross and Net Weight of Hogs. - It is assumed that the gross wight of hogs diminished 1/5 or 20% of itself, give the net weight and the net weight increases by 1/4 or 25% of itself equals the gross weight. Thus: If the gross weight of a load of hogs is 1800 pounds, the net weight would be 1/5 or 360 less, or 1440 pounds. If the net weight is 1440 the gross weight will be 1/4 or 360 pounds more or 1800 pounds.

12. How to Find the Number of Yards of Carpet to Cover a Floor - Multiply the length of the room in feet by the width in feet and divide the results by 9, and you have the number of yards of carpet required, if the carpet is one yard wide. If the carpet is only 3/4 of a yard wide proceed as above, and then multiply by 4 and divide by 3.

13. An Easy Way to Multiply by 11 - To multiply any two figures by 11, add the two figures together and place their sum between the two figures of that number. If the sum of the two figures exceed 9, the left hand figure must be increased by 1.

14. How to Find the Number of acres in a Field - If the field is rectangular, multiply the length in rods by the breadth and divide by 160. If the piece is triangular, multiply the length in rods by the breadth and divide by 2. Then divide by 160 and the result will be the number of acres in the field.
1. Example how many acres in a piece of land 90 rods long and 20 rods
wide? 80 x 20 = 1600 1600 divided by 160 = 10 acres.
2. Example how many acres in a triangular field 80 rods long and 40 rods wide: 80 x 40 divided by 2 = 1600 sq. rods, 1600 divided by 160 = 10 acres.

15. How to Measure Wood - Multiply the length, breadth and height in feet together, and divide by 128. The result will be the number of cords. Example. How many cords in a pile of wood 20 feet long, 4 feet wide, and 8 feet high? 20 x 4 x8 =640 640 divided by 128=5cords

16. How to Find the Number of Shingles Required for a Roof - Multiply the length of the roof by twice the length of one rater, and multiply the result by 8 if the shingles are to be exposed 4.5 or, by 7 if the shingles are to be exposed 5 inches to the weather and you will have the number of shingles required.