18. .2 x .3 x 1x0 =? 19. If you receive .05 of what you collect, how much will you receive for collecting $32? 20. What part of 27 is 9? Express the answer decimally. 21. Howard and Fred each earned .8 of a dollar. ¿ Howard spent .5 of a dollar at the circus. How much had he left? Fred spent .5 of his money in car rides. How much had he left? 34. George earned $2 one day and $.2 the next. much did he earn in both days? How 35. Richard had $2 and spent $.2. How much had he left? 36. Robert had $2 and bought neckties at $.2 each. How many did he buy? 37. Frank bought 2 baseballs at $.2 each. How much did he pay for them? 38. Mr. Atkinson had 5 acres of land. How much had he after buying .5 of an acre from his neighbor? 39. Mr. Blake had 5 acres and sold .5 of an acre. How much had he left? 40. Mr. Sayles sold .5 of a pasture containing 5 acres. How many acres did he sell? 41. A field containing 5 acres was cut up into lots of .5 of an acre each. How many lots? LINEAR MEASURE Oral A straight line is the shortest distance between two points. A line has one dimension-length. Linear or Long Measure is used in measuring lengths The sign for feet. "' is frequently used for inches, and the sign' Thus, 2' 6" means 2 feet 6 inches. 3. How many inches in 1 ft. 3 in.? 2 ft. 8 in.? 3 ft. 4 in.? 4 ft. 2 in.? 5 ft.? 6 ft. 6 in.? 2 ft.? 15 ft.? 4. How many inches in yd.? 5. How many feet in 13 yd.? 23 yd.? 6. Express yd.? { yd.? } yd.? 14 yards as feet; 14 feet as yards. 7. What part of a yard is 1 ft.? 2 ft. ? 11 ft.? 1 ft. 3 in.? 1 ft. 8 in.? 2 ft. 6 in.? 8. Leon is 52 inches tall. How 9. How tall are you? How many feet? 10. What is the height of the tallest boy in the room? Of the shortest boy? What is the difference in their heights? 11. How many inches from the floor is your desk? Your chair? 12. Make other measurements about the schoolroom. Express as parts of a mile: 1. How many telegraph poles, placed 10 rods apart, are required to string a mile of telegraph wire ? 2. How much will the wire in problem 1 cost at of a cent a foot? TABLE OF SQUARE OR SURFACE MEASURE 87 3. A gymnasium running track measures 16 laps to a mile. How many rods to a lap? What part of a mile does Victor run in making 5 circuits? 4. How many rods around a rectangular field 100 rods. long and 60 rods wide? What name is given to this number of rods? 5. David runs a 100-yard dash in 12 seconds. How many feet a second? 6. A hand is 4 inches. A horse 14 hands high is how many feet high? 7. A passenger car is 70 feet long. How many yards? How many rods? 8. Blanche lives 3168 feet from the schoolhouse, Ruby 200 rods, and Alice of a mile. Who has the longest walk? Who has the shortest walk? SQUARE OR SURFACE MEASURE A surface has two dimensions-length and width. 1. Learn: TABLE OF SQUARE OR SURFACE MEASURE 144 square inches (sq. in.) = 1 square foot (sq. ft.) 9 square feet 30 square yards] or 272 square feet 160 square rods 640 acres = 1 square yard (sq. yd.) The area of a surface is the number of square units it contains. 3. How many square feet in a rectangle 4 feet long and 1 yard wide? What is the unit of measurement? How many of these units in 1 row? In all the rows? Short method: 3 x 4 12. Think first of the unit of measurement. The area of a rectangle can always be found by multiplying together its length and its width, when both are expressed in the same unit of measurement (inches, feet, yards, etc.). NOTE. While, for convenience, we say that we multiply the two dimensions together, it must be noted that this is not strictly true. We cannot say that 3 feet times 4 feet equals 12 square feet any more than we can say that 3 eggs times 4 eggs equals 12 square eggs, since the multiplier is always an abstract number and simply tells the number of times a quantity is taken. What we mean is that, since the unit of measurement is 1 square foot, we have in one row 4 of these units, or 4 square feet; in 3 rows we have 3 times 4 square feet, or 12 square feet. |