19 times 20 times 21 times 22 times 23 times 24 times 1 are 19 1 are 20 1 are 21 1 are 22 1 are 23 are 21 13 times 14 times 15 times 16 times 17 times 18 times 19 times 20 times 21 times 22 times 23 times 24 times 13 are 247 13 are 260 13 are 273 13 are 286 13 are 299 13 are 312 EXPLANATION -These Tables are designed for a brief exercise at the beginning or close of the daily recitation, and should be dwelt upon until the pupil is familiar with the various combinations. Let the pupil recite the table assigned to him, as the signs indicate; thus, in No. 1, 4 and 3 are 7, 5 and 6 are 11, etc.; in No. 16, 13 less 4 are 9, etc.; in No. 31, 6 times 8 are 48, etc.; in No. 46, 4 in 36, 9 times, etc. The tables may be profitably used in many ways. The columns may be added upward or downward, or substituting + for --, X, and ÷, add across the page. Substituting for, the table for division becomes a table for subtraction. By dividing the dividend of one example by the divisor of another, mixed numbers may be obtained; thus, in Nos. 46 and 47, say 4 in 25, 5 in 36, 7 in 48, etc. WRITTEN ARITHMETIC. 1. ON page 26 the pupil nas learned the names and meaning of the tea Arabic figures, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9; and on page 27 he has learned the names and uses of the signs, $,,, −, ×, ÷ 2. The learner has also doubtless observed that the value of a figure depends not only on the figure itself, but also on the place the figure occupies; for example, 4, standing alone, means four units, or ones; but when the 4 is made to occupy the second place, by putting 0 or any other figure on the right of it, it becomes four tens; thus, 40 equals four tens, or forty; 46 equals four tens plus six, that is, forty-six, etc. Again, when two figures are at the right of 4, the 4 becomes four hundreds, which equals ten times four tens; that is, each remove of a figure one place toward the left makes its value ten times as much as it was before. This will be seen in the following Table : Two hundred and twenty-two thousand, two hundred and twenty-two. Five thousand four hundred and ninety-six. Sixty thousand, two hundred and forty-three. Six hundred and one thousand, three hundred and five. 1. Forty-seven. 2. Sixty. 3. Two hundred and seventy-nine. 4. Five hundred and eight. 5. Three thousand, five hundred and sixty-two. 6. Eight thousand and two hundred. 7. Sixty-two thousand, five hundred and twenty. 8. One hundred and six thousand, two hundred and four. 9. Four hundred thousand, four hundred and thirteen. 5. ADDITION. BY ADDITION we find how many units there are in two or more numbers taken together. The result of the addition is called the SUM, or AMOUNT. 6. To add when the amount of each column is less than ten. Ex. 1. A farmer sold 125 bushels of corn, 342 bushels of oats, and 231 bushels of wheat; how many bushels of grain did he sell? Ans. 698. OPERATION. 125 342 231 Having set the numbers so that units stand under units, tens under tens, etc., add the units; thus, 1 and 2 are 3, and 5 are 8, and set the 8 under the column of units. Then add the tens; thus, 3 and 4 are 7, and 2 are 9, and set the 9 under the column of tens, and so proceed till all the columns are added. Sum, 698 |
