22. Periods. Trillions. Billions. Millions. Thousands. Units. 15th. Hundred Trillions. 14th. Ten Trillions. 13th. Trillions. 12th. Hundred Billions. 11th. Ten Billions. 10th. Billions. 9th. Hundred Millions. 8th. Ten Millions. 7th. Millions. 6th. Hundred Thousands. 5th. Ten Thousands. 4th. Thousands. 3rd. Hundreds. 2nd. Tens. 1st. Units. Orders of Units, 5 4 3 2 10 9 8 7 6 5 4 3 2 1 The above number is read Five hundred forty-three trillions, two hundred ten billions, nine hundred eightyseven millions, six hundred fifty-four thousands, three hundred twenty-one. In writing large numbers, the comma is generally used to separate periods. 23. Read the following numbers : 24. Write in figures the following numbers, placing figures of the same order in the same column; then read the numbers: 1. Two thousand fifty. 2. Sixteen thousand three hundred four. 3. Twenty thousand sixty. 4. Three hundred thousand sixteen. THE NEW MODEL ARITHMETIC. CHAPTER I. NOTATION AND NUMERATION. Article 1. The system of writing numbers which is in general use, and which is called Arabic Notation, employs 2. NAMES: Six. Seven. Eight. Nine. The figures 1, 2, 3, etc., represent one unit, two units, three units, etc. The figures from 1 to 9 inclusive are called digits. The figure 0, named zero, naught, or cipher, denotes absence of number, or no number. 3 A number greater than nine is expressed by two or more 4. Ten is composed of ten units, just as a dime is equal in value to ten cents. Ten units, or one ten, are written 10. The figure 1 here occupies tens' place, that is the second place, counting from the right. The figure 0 stands in units' place, that is, the first place, counting from the right, and denotes no number in units' place. 5. The number eleven, 11, is composed of 1 ten and 1 unit: 10+1=11. The number twelve, 12, is composed of 1 ten and 2 units : 10+2=12. Of what are the numbers 12, 13, 14, 15, etc., respectively composed? 6. The number twenty, 20, is composed of two tens: 10+10 =20. Thirty, 30, is three tens, 10+10+10=30. Of what is forty composed? Fifty? Sixty? etc. 7. Units may be arranged in groups of ten each, and may be counted by tens, thus: 8. The number twenty-one, 21, is composed of 2 tens and 1 unit: 20+1=21. Twenty-five, 25, is composed of 2 tens and 5 units: 20+5=25. Of how many tens and units is each of the following numbers composed? 28? 31? 34? 39? 53? 63? 69? 70? 80? 89? 98 ? 9. Read the following numbers : IO. 9, 19, 21, 26, 33, 48, 51, 57, 62, 68, 75, 79, 86, 99. Write in figures the following numbers: 1. Seven. 2. Seventeen. 5. Twenty-six. 9. Sixty-seven. 3. Seventy. 6. Sixty-two. 7. Thirty-four. 4. Seventy-one. 8. Forty-three. 10. Sixty-nine. 11. Eighty-four. 12. Ninety-six. II. Ten tens are one hundred, 100; that is, one hundred units. The figure 1, in 100, occupies hundreds' place, that is, the third place counting from the right the two zeros, 00, show that there are no units in tens' place and in units' place. The hundred units are considered as grouped into one group, or body, called a 12. hundred, just as a dollar is equal in value to ten dimes, or one hundred cents. Units may be arranged in groups of ten tens, or one hundred units, and may be counted by hundreds, One hundred. Two hundred. Three hundred. Four hundred. etc. 13. The number one hundred one, 101, is composed of 1 hundred, no tens, 1 unit: 100+00+1=101. The number one hundred ten, 110, is composed of 1 hundred, 1 ten, no units: 100+10+0=110. The number one hundred twenty-five, 125, is composed of 1 hundred, 2 tens, 5 units: 100+20+5=125. Of how many hundreds, tens and units, is each of the following numbers composed: 153? 246? 379? 600? 709? 840? 14. Read the following numbers: 116, 149, 270, 309, 465, 555, 679, 843, 989. 15. Write in figures the following numbers: 1. One hundred twenty. 2. One hundred two. 5. Five hundred ninety-six. 6. Seven hundred seven. 3. Two hundred twenty-one. 7. 4. Three hundred sixty-three 8. Nine hundred nine. 16. These three places, or orders, that is, units, tens, and hundreds, constitute the period of units, or, the units' period. What is the largest number, that is, whole number, that can be expressed in units' place? What is the largest number that can be expressed in tens' and units' places? In the period of units? 17. Ten hundreds compose the number one thousand, 1000. |