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Write the following numbers in figures:

1. Twenty-two thousand seven hundred sixty-five. 2. Eighty thousand two hundred one.

3. Thirty thousand thirty.

4. Four hundred ten thousand two hundred five. 5. Ninety thousand one.

6. Eight hundred thousand six hundred sixty-nine.

7. Nine hundred thousand one.

8. Five hundred thousand fifty.

9. One hundred million ten thousand one. 10. Ninety-one million seven thousand sixty. 11. Seventy million four.

12. Seven hundred million ten thousand one. 13. One billion one million forty.

14. Forty billion two hundred thousand five.

15. Seven hundred twenty-six billion fifty million one thousand two hundred forty-three.

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43. In the Roman Method numbers are expressed by means of seven characters.

44. The Roman method of expressing numbers had its origin in Rome.

45. The Characters used in this system of expressing numbers are seven Letters.

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47. When used alone each letter has a fixed value.

48. When a letter is repeated, its value is repeated. Thus, III are 3, XX are 20, CCC are 300, MM are 2000.

49. When a letter follows one of greater value, their sum is the number expressed. Thus, VI are 6, LX are 60.

50. When a letter precedes one of greater value, their difference is the number expressed. Thus, IV are 4, XL are 40.

51. When a letter is placed between two others of greater value, the difference between it and their sum is the number expressed. Thus, XIX are 19, XIV are 14.

52. When a horizontal line is placed over a letter, its value is increased a thousand times. Thus V is 5000.

53. Uses.-Roman notation is not convenient for arithmetical computations, but is used principally in marking dials, numbering chapters, sections, &c., in books, and in writing physicians' prescriptions.

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SECTION III.

ADDITION I

54. Addition is the process of uniting two or more numbers to form one number.

The Terms used in Addition are Addends, or Parts, and Sum, or Amount.

55. The Addends, or Parts, are the numbers to be added.

56. The Sum, or Amount, is the result obtained by Addition.

57. Signs are characters used for abbreviating expressions.

58. The Sign of Addition is an erect cross called plus (+), and when placed between numbers signifies that they are to be added. Thus, 3 + 2 means that 3 and 2 are to be added, and is read "3 plus 2."

The term plus, Latin, signifies more, or added to.

59. The Sign of Equality is two short, horizontal, parallel lines (=), and when placed between numbers signifies that they are equal. Thus, 3 + 2 = 5 means that 3 and 2 are equal to 5, and is read "3 plus 2 equals 5."

60. The Sign of Dollars is a capital S with two vertical marks across it ($), and when placed before a number expresses dollars. Thus, $120 means 120 dollars.

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