7. Find the volume of a solid 10 in. long, 6 in. wide, and 4 in. thick. How many square inches in its surface ? The unit in Wood Measure is the cord. It consists of a pile of wood 8 ft. long, 4 ft. wide, and 4 ft. high, and therefore contains 8 x 4 x 4, or 128 cu. ft. The cord foot is one foot in length of such a pile, or 16 cu. ft. 8. A cord foot is what part of a cord ? 9. How many cord feet make a cord ? 10. How many cord feet are there in 32 cu. ft. ? In 48 cu. ft. ? 11. 48 cu. ft. equal what part of a cord ? LESSON 122 OPERATION 1. How many cords are there in a pile of wood 24 ft. long, 12 ft. high, and 4 ft. wide ? The number of cubic feet in the pile = 24 x 12 x 4, or 1152. Divid- 24 x 12 x 4 = 1152 cu. ft. in pile. ing 1152 by 128, the number of 1152 · 128 = 9 cords. cubic feet in a cord, we get 9, the number of cords. 2. How many cubic feet are there in a pile of wood 32 ft. long, 4 ft. wide, and 4 ft. high? How many cord feet? How many cords? 3. How many cords of wood are there in a pile 32 ft. long, 91 ft. high, and 4 ft. wide? How much is the wood worth at $4 a cord ? 1 foot -1 foot 4. How many cords of wood can be put into a shed 24 ft. long, 16 ft. wide, and 12 ft. high? How much is the wood worth at $4.50 a cord ? 5. Find the number of cubic yards of earth that will have to be removed in digging a cellar 24 ft. long, 18 ft. wide, and 6 ft. deep. What will be the cost at 30¢ a load (1 cu. yd.) ? The unit in Board Measure is the board foot. The board foot is a square foot one inch thick. 6. How many board feet are there in a piece of board 2 ft. long, 1 ft. wide, and 1 in. thick ? footh 7. Find the number of board feet in a board 15 ft. long, 16 in. wide, and 1 in. thick. The shape of the board is that of a rectangle. To find the area of a rectangle we multiply the 16 : 12 =1}, width of board in ft. length by the width. 1} x 15 = 20 board feet. A board 14 in. thick contains 14 times as many board feet as a board 1 in. thick, and a board 11 in. thick contains 14 times as many. 8. Find the number of board feet in a board 18 in. wide, 16 ft. long, and 11 in. thick. Since the board is 14 in. thick, it contains 14 times as many 18 = 12 = 1}, width of board in ft. board feet as a board 1 inch 11 x 16 x 14 = 30 board feet. thick. 9. How many board feet are there in a board 2 ft. long, 6 in. wide, and 1 in. thick ? 10. How many board feet are there in a board 2 ft. long, 1 ft. wide, and 2 in. thick ? OPERATION OPERATION LESSON 123 1. How many board feet equal a cubic foot ? 2. How many board feet are there in a board 12 ft. long, 1 ft. wide, and 2 in. thick? How many cubic feet ? 3. A board 6 ft. long, 1 ft. wide, and 1 in. thick is what part of a cubic foot ? 4. How many board feet are there in a board 8 ft. long, 1 ft wide, and 12 in. thick ? 5. How many board feet are there in a board 10 ft. long, 1 ft. wide, and 2 in. thick ? 6. How many cubic feet are there in a board 16 ft. long, ft. wide, and 1 in. thick ? 7. How many board feet equal 4 cubic feet? 6 cubic feet? 8. 5 cubic feet equal how many board feet ? 9. How inany board feet are there in a board 18 in. wide and 12 ft. long ? 10. How many board feet are there in a board 15 in. wide, 16 ft. long, and 1 in. thick? In a board 15 in. wide, 20 ft. long, and 12 in. thick ? 11. Find the number of cords in a pile of wood 32 ft. long, 8 ft. high, and 4 ft. wide. Find the cost of the wood at $5.60 a cord. 12. How many board feet are there in 12 boards, each 16 ft. long, 1 ft. wide, and 1 in. thick? 13. Find the number of board feet in 25 boards, each 12 ft. long, 18 in. wide, and 1 in. thick. 14. Find the cords in a pile of wood 40 ft. long, 12 ft. high, and 41 ft. wide. INTEREST LESSON 124 If you use land or a house belonging to another person, the money you pay for the privilege is called rent. If you obtain the use of another's money, the sum you pay for its use is called Interest. The money loaned is called the Principal. Interest is always calculated at a certain per cent of the principal for one year, unless otherwise stated. For example, interest at 6% means that the interest for one year is 6% of the principal. Interest at 5% means that the interest for one year is 5% of the principal. If I borrow $1 for a year and agree to pay 6% interest, I must pay 6% of $1.00, or 16 of $1.00, or 6¢ interest. 1. If I pay 6¢ for the use of $1 for 1 year, how much interest must I pay if I keep it 2 yr.? 3 yr.? 4 yr.? 51 yr.? 2. If the interest of $1 for 1 yr. is 6%, how much is the interest of $5 for a year? 2 yr.? 3 yr.? 41 yr.? 3. If the interest of $1 for 1 yr. is 66, how much is the interest of $10? $12? $22 ? 4. At 4%, what is the interest of $1 for 1 yr.? 2 yr.? 3 yr.? 31 yr.? 5. At 6%, what is the interest of $4 for 1 yr.? 3 yr.? 21 yr.? 6. What is 6% of $100? $ 200 ? $300? $250 ? 7. What is the interest of $100 for 1 yr. at 6%? For 2 yr.? For 6 mo. (1 yr.)? 8. What is the interest of $1 for 1 yr. at 5% ? For 2 yr.? For 6 mo.? 9. At 5%, how many dollars must I lend to receive 50¢ interest at the end of a year? 10. At 7%, how many dollars must be on interest to yield $ 1.40 interest ? LESSON 125 1. What is the interest of $40 for 3 yr. at 5%? MODEL. 5% = 18, or zb. 2. Find the interest of $60 for 4 yr. at 5%. 8. Find the interest of $300 for 3 yr. at 6%. 10. Find the interest of $200 for 2 yr. 8 mo. (2 yr.) at 6%. 11. Find the interest of $ 200 for 2 yr. 9 mo. (24 yr.) at 6% 12. What is the interest of $ 800 for 1 yr. at 4%? 5%? At 3%? 13. What is the interest of $600 for 2 yr. 6 mo. at 3%? For 2 yr. 4 mo.? For 2 yr. 8 mo.? For 2 yr. 10 mo. (26 yr.) ? |