RULE. Having placed units under units, tens under tens, &c. draw a line underneath, and begin with the units : Af. ter adding up every figure in that column, confider how many tens are contained in their sum, and, placing the excess under the units, carry so many, as you have tens, to the next column, of tens : Proceed in the same manner through every column, or row, and set down the whole amount of the last row. PRÒ O F. Begin at the top of the fum, and reckon the figures downwards, in the same manner as they were added upwards, and, if it be right, this aggregate will be equal to the first. Or, cut off the upper line of figures, and find the amount of the rest ; then, if the amount and upper line, when added, be equal to the sum total, the work is supposed to be right. ADDITION and SubtrACTION TABLE. 2 21 31 41 51 61 71 8 9 10 11 12 41 51 671 81 910111213114 3 51 61 71 8 9 10 11 12 13 14 15 41 61 71 81 9110111213141516, 51 71 81 911011121311 11|12|13|14115116117 6 8 9 10 11 12 13 14 15 16 17 18 711 9 10 11 12 13'14!1516,17,18,19 8101112131415116117118119120 II'121314151617,1819120121 10]!21314115.1617.1819 20121/22 When you would add two numbers, look one of their in the left hand column, and the other atop, and in the B common common angle of meeting, or, at the right hand of the first, and under the second, you will find the sum-as, 5 and 8 is 13. When you would subtract : Find the number to be subtracted in the left hand column, run your eye along to the right hand till you find the number from which it is to be taken, and right over it, atop, you will find the difference--as, 8, taken from 13, leaves 5. 1 7 1234567 2345678 3456789 4567890 5678209 6789098 9. 1234567 9876543 2102865 4321234 5682098 6543218 1234567 723456 34565 4566 333 90 67 123 4567 89093 654321 1234567 SUBTRACTION SUBTRACTION Teaches to take a less number from a greater, to find a third, shewing the inequality, excess or difference between the given numbers ; and it is both simple and cɔmpound. SIMPLE SUBTRACTION ACTiON Teaches to find the difference between any two numbers, which are of a lise kind. RUL E. Place the larger number uppermost, and the less u!)derneath, so that units may stand under units, tens under tens, &c. then, drawing a line underneath, begin with the units, and subtract the lower from the upper figure, and fet down the remainder ; but if the lower figure be greater than the upper, borrow ten, and subtract the lower figure therefrom : To this difference, add the upper figure, which, being set down, you must add one to the ten's place of the lower line, for that which you borrowed ; and thus proceed through the whole. PROOF. In either simple, or compound Sabtraction, add the remainder and the less line together, whose fum, if the work be right, will be equal to the greater line : Or, subtract the remainder from the greater line, and the difference will be equal to the less. EXAMPLES May be accounted the most serviceable Rule Aritha metic. It teaches how to increase the greater of two numbers given, as often as there are units in the less ; performs the work of many additions in the most compendious manner ; brings numbers of great denominations into small, as pounds into shillings, pence or faritings, &c. and, by knowing the value of one thing, we find the value of inany. It consists of three parts. 1. The Multiplicand, or number given to be multiplied, and, commonly, the largest number. 2. The Multiplier, or number to multiply by, commonly, the least number. 3. "The Product is the result of the work, or the an. swer to the question. SIMPLE MULTIPLICATION Is the multiplying of any two numbers together, without having regard to their fignification, as 7 times 8 is 56, &c. MULTIPLICATION and Division TABLE. 2 IO I2 12 Il 2 | 3 | 4 | 5 | 6 | 7 | 8 9 10 11 12 4 6 8 12 14 16 18 20 22 24 3 15 18 | 21 241 271 301 33) 36 16 20 | 24 | 28 | 32 36 40 441 48 5 | 10 | 15 20 | 25 50 551 60 6 | 12 | 18 24 | 30 | 36 | 42 | 481 54 601 661 72 7 | 14 21 28 / 35 | 42 | 49 | 56 63 701 77 84 8| 16 | 24 32 | 40 | 48 | 56 | 641 72 801 881 96 9 18" 27 | 36 | 45 | 54 | 63 | 721 81 901 9911081 10 20 30 40 50 60 70 80 90 100 110 120 22 | 33 | 44 | 55 | 66 | 77 | 881 99|110121|132 1224 36 | 48 | 60 | 72 | 84 | 96 108/1201132|144) II To learn this Table, for Multiplication : Find your multiplier in the left hand column, and your multiplicand atop, and in the common angle of meeting, or against your multiplier, along at the right hand, and under your multiplicand, you will find the product, or answer. To learn it, for Divifon : Find the divisor in the left hand column, and run your eye along the row to the right hand until you find the dividend ; then, directly over the dividend, atop, you will find the quotient, shewa ing how often the divisor is contained in the dividend. |