21. What will 5 feet 9 inches of wire railing cost, at (2.) Find cost of 1 inch. (3.) Find cost of 9 inches. ANALYSIS. (1.) Since 1 ft. costs $1.50, 5 ft. will cost 5 times as much; or, $7.50. (2.) Since 12 inches (1 ft.) costs $1.50, one inch will cost one-twelfth as much; or, $.125. (3.) Since 1 inch costs $.125, nine inches will cost 9 times as much; or, $1.125. (4.) The total cost will be the sum of $7.50 and $1.125; or, $8.625. 22. What will 4 yards and 1 foot of brass wire cost, at 12 cents a yard? W. What will 17 yards 2 feet cost, at 18 cents a yard? 23. At 36 cents a yard, what will 2 feet of cloth cost? W. What will 7 yards, 6 inches cost? 14 yards, 2 feet, 6 inches? 13 yards, 2 feet? 24. W. At $1.80 a rod, what will 7 rods and 2 yards of stone fence cost? 4 rods and 4 yards? 25. W. What will it cost to fence a piece of land 18.24 chains long and 11.38 chains wide, at $1.10 per rod? REVIEW.-What is meant by the simple value of a figure? (10.) By the local value of a figure? (11.) What is numeration? (12) What is the use of ciphers in writing a number? Repeat the numeration table by periods from right to left. From left to right. If you will take a piece of paper, like the one on the board in the picture, one foot square, and divide it into 12 rows of squares, with 12 squares in each row, making 144 pieces of equal size, each piece will contain just one square inch. It will take 9 square feet of paper to cover the surface of the board, which contains a square yard. The grass-plat in the door-yard is 30 times as large as the surface of the board, and contains one square rod. The field in which you see the sheep is 160 times as large as the grass-plot, and contains one acre of land. 119. Square Measure is used for calculating areas of land, roofing, flooring, paving, painting, &c. REVIEW. How many units of any order make one of the next higher? (13.) How does a change of one place to the right affect the value of a digit? How does a change of one place to the left affect its value? = = = 1 square rod (sq. rd. or pch.). 1 square chain (sq. ch.). (A.). (sec.). (T.) 1 acre 1 section 1 township A section is a piece of land a mile square, and is equal to a square mile. Exercise. I. (See Drill Card, Table VI.) Reduce V acres to square rods. II. Reduce V square rods to square yards. VIII. Reduce X. sections to townships. Prepare the above exercises in the same manner as on page 205, the results to be read as a class-exercise. 1. In the above illustration is seen a room 24 feet long, 21 feet wide, and 18 feet high: what is the size of the room in yards? How many square yards in the first row on the right side of the room? How many square yards in the entire floor? ANALYSIS. Since in 1 row (of square yards) there are 8 square yards, in 7 rows there are 7 times 8 square yards; or, 56 square yards. 2. How many square yards in the right hand wall? How many square yards in the left hand wall? How many in the end wall? How many in the ceiling? How many walls in a room? How many floors? How many ceilings? 3. How many square yards in the two side walls? How many in the two end walls? How many in all the walls taken together? 4. Since there are 9 tiles one foot square in each square yard, how many tiles in one row of square yards? How many in the entire floor? ANALYSIS. (1.) Since in 1 square yard there are 9 tiles, in 8 square yards (1 row) there are 8 times 9 tiles; or, 72 tiles. (2.) Since in 1 row of 8 yards there are 72 tiles, in 7 rows (the entire floor) there are 7 times 72 tiles; or, 504 tiles. 120. TO FIND THE AREA OF A SQUARE OR PARALLELOGRAM: RULE. Multiply the length by the breadth, and the product will be the area. NOTE. — Usage, and the want of any other equally terse form of language, sanction this rule. Logically it is not true, any more than multiplying deer by grain will produce buckwheat. If the argument of the above paragraphs is thoroughly understood, the form of the rule can do no harm. Artificers usually estimate their work 1. By the square foot; as in stone-cutting. 2. By the square yard; as in papering, lathing, plastering, paperhanging, &c. 3. By the 100 square feet; as in flooring, roofing, siding, slating, &c. 4. By the thousand bricks, or by the square yard; as in bricklaying. WRITTEN EXERCISES. 26. How many square inches in a cardboard 5 inches long and 3 inches wide? 15 square inches. FORMULA. 5 square inches × 3 (rows) = ANALYSIS. Since in one row (5 inches long) there are 5 square inches, in 3 rows (3 inches wide) there are 3 times 5 square inches; or, 15 square inches. REVIEW. - Define a rule. (14.) Recite the rule for notation. (15.) Recite the rule for numeration. (16.) Define addition. (17.) |