.137 142 143 145 146 Mental Arithmetic .. 149 Explanation of the Characters used in this work. = Equal to. The sign of Equality; as 4 farthings that is, 4 farthings are equal to 1 penny. + Plus, or more. The sign of Addition; as 3 + 2 = 5, that is 3 added to 2, = 5. x Into. The sign of Multiplication; as 5 X 4 = 20, that is, 5 multiplied into 4 = 20. • By. The sign of Division; as 6 = 2 = 3, that is, 6 divided by 2 = 3. : Is to | The signs of Proportion; as 2: 4::8: 16, that is, as 2 is to 4, so is 8 to 16. :: Sois The sign of Contraction, or cancelling, which implies that the numbers 18 and 12 have been struck out, and the numbers 3 and 2 are to be used instead. ARITHMETIC is the Science of computing by Numbers. Its leading Rules are NUMERATION, ADDITION, SUBTRACTION, MULTIPLICATION, and Division. NUMERATION Teaches to read the value of numbers : Thus, 23 is read, Twenty-three. 756 is read, Seven hundred and fifty-six. EXERCISES FOR THE LEARNER. Write in words the following, 42—87–153—604. rated thus : 2,340 Two thousand, three hundred and forty. 50,129 Fifty thousand, one hundred and twenty-nine. 718,406 Seven hundred and eighteen thousand, four hundred and six. EXERCISES. When there are more than six figures, they are numerated thus : 3;209,186 Three millions; two hundred and nine thousand, one hundred and eighty-six. 54;072,831 Fifty-four millions; and seventy two thousand, eight hundred and thirty-one. 908;375,200 Nine hundred and eight millions; three hundred and seventy-five thousand, two hundred. Note. The figures between each stop are read as if they stood alone ; those before a comma being always thousands, and those after the comma being millions, billions, trillions, &c., according to their place: Thus, in the Table 987;654,321 are read, 987 millions; 654 thousands, 321. EXERCISES. Write in words 1;285,362—40;237,615–327;805,463—901;004,350. In common calculations more than nine figures are seldom required. But the Table may be extended to any length; as millions, billions, trillions, quadrillions, quintillions, &c. Thus, 32;407,280;375,049 are read, Thirty-two billions ; four hundred and seven thousand, two hundred and eighty millions; three hundred and seventy-five thousand, and forty-nine. NOTATION Thus, Forty-seven is written... 47 EXERCISES. Write in figures the following, Fifty-four - Eighty-nine — Two hundred and thirty-six. When the number contains thousands Thus-Five thousand, two hundred and forty, is written.... 5,240 Eighty-four thousand, and thirty-seven. 84,037 Six hundred and ninety-one thousand, two hundred and seventy-five...... 691,275 EXERCISES. Express in figures, Three thousand, one hundred and eighty-four. Forty-nine thousand, two hundred and eight. Six hundred and seventy-three thousand, one hundred and seventynine. |