Arizona republican., 1898-01-13
AGRICULTURAL.
THE FARMERS ARITHMETIC.

THE FARM EiSS AftIl lf1MElIC.
 In a crib, as in the wagon box, it reuuires two and one-half cubic feet to contain one bushe1 of ear corn when the crib is newly filled. To estimate feet and the product by the height in the amount of corn in crib, all that is necessary is to multiply the length of the crib in feet by the breadth in feet and divide by two and o1e-half, the number of cubic feet in bushel of ear corn. Say that crib is Is feet long, 8 feet wide and 8 feet high, we have 16 multiplied by 8, multiplied by 8 equals 1,O24 and 1,024 divided by 21s gives us the number of bushels, 4O9 3-5. In dividing by mixed num- Der, as 21s, it is well 10 remember that the division is readily done by reduc- ing both numbers to the same denoml- nation. Thus 21k is reduced to hayes by multiplying the whole number Z, by the denominator of the fraction, Z, and adding the one which makes 0 and by multiplying 1,O24 by 2, both dividend and divisOr being then of the same denomination, halves, the division can be readily and accurately accomplished. But corn cribs are not always built in such manner that the length, width and height are in even feet, and when inches are involved the work of estimating the contents becomes more difficult To those who are familiar with fractions, it is an easy matter to multiply and divide both by feet and by inches but as there are many who cannot readily apply fractions, either common or decimal, duodecimals offer a simple method of making computations, when feet and inches are included. In many of our school arithmetics this rule is now omitted, but in measuring corn cribs and grain bins it affords a ready means of obtaining the solid con tents. As the name implies a scale of twelfths is used, being two added 10 the decimal ten, and in measuring sur face or solids, the work can be readily performed by any one familiar with the simple rules of arithmetic AS the winter term of our district school is now in session, and the evenings are long, the boys on the farm will find it both interesting and profitable to apply their knowledge of arithme- tic in estimating the contents of corn cribs and grain bins, and pracical work of this kind prove of far more utility than when confined to the ex- amples furnished by the arithmetic. Say that corn crib is sixteen feet seven inches in length, eight feet three inches in width, and seven feet ten inches in height. Instead of reducing the feet to inches, as usually dore by farmers nQt familiar with frac ions, we will apply the rule of duodecimals and multiply the length sixteen feet seven inches, by the width feet inches. In multiplying feet by feet we obtain square feet, and multiply ing inches we obtain square inch s, which to reduce to feet must be divid- ed by IA the number of square inches in foot. With duodecimals. all the divisions are done by 12, so that the work can be done mentally and dividing by 12 twice, is piac i- cally the same as dividing by IA. In multiplying feet by inches it is only necessary to divide by 12 once to ob- tain square feet, and for convenience we begin the work by multiplying first by the feet and next by the inches. Assuming that you have paced the l6 feet inches and that the feet 8 inches in proper manner, feet be- meath feet and inches beneath inch S. not forgetting to draw a line beneath, we begin by multiplying the inches by feet and we have 56 as the result. Dividing by 12 there is found to be square feet and 8 inches of a remain der. The 8 inches are placed in the proper place and the Is is now multi plyed by the number of feet, which is 8, and we have the result 128 to which is added the 4 heretofore ob- tained making 132 feet which is p,ac- ed in the proper place. We next null t1ply the number of inches together. saying times are 21 and dividing by 12 we have 1 and of a remainder. The remainder is placed one space TO the right, and the Is, the number Of feet is multiplied by 3, which gives 4S, which with the one added. makes 49, and this sum divided by 12 gives 4 feet and 1 inch, which are placed 11 their respective places. Adding these numbers together, we have 136 feet, g inches and g twelfths of an inch. This is now the square surface in feet, and by multiplying in like manner by the height in feet and inches the solid contents are obtained. In practice feet and inches are suffic- 1ently accurate for all practical pur- poses, and by dividing by 21h, as be- fore explained, the number of bushels is quickly ascertained.