First Lessons in Mental and Written Arithmetic; On the Objective Method

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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1871 edition. Excerpt: ... we write 5 once By Addition, only; and, since it is to be taken 3 5 + 5 + 5 = 13. times and added, we write 3 at the right of 5, and, turning the Sign Second Solution. Plus thus, x, place it between the By Multiplication. 5 and 3. The whole stands thus: 5 x 3 = 15 5 x 3 = 15; and is read: 5 multiplied by 3 equal 15. When the Sign Plus is thus turned and used it does not show that 5 and 3 are to be added together, but shows that 5 are to be taken 3 times and added, to find the Sum; or, which means the same, it shows that 5 are to be multiplied by 3. For this reason, when the Sign Plus is thus turned and used we name it the Sign of Multiplication. The Sign of Addition is a Vertical Cross. The Sign of Multiplication is an Inclined, Cross. We can write 6 multiplied by 3 equal 18; or 6 x 3 = 18; 9 multiplied by 3 equal 27; or 9 x 3 = 27. Write, learn, and recite, the following Partial Products. LESSON LXI. Example A. Multiply 879 by 3. Explanation. First; we multiply 9 Ones by 3, and write the Product, 27 Ones. We name this a Partial Product, because it forms only a part of the true Pro-Bolutioh. duct. Second; we multiply 7 879 Multiplicand. Tens by 3, and, having 21 Tens, Multiplier. or 2 Hundreds and 1 Ten, for 271 our second Partial Product, 21 r write 1 Ten in the column of J Tens, and 2 Hundreds at the 2,637 Product. left, in the column of Hundreds. Third; we multiply 8 Hundreds by 3, and, having 24 Hundreds, or 2 Thousands and 4 Hundreds for our third Partial Product, write 4 Hundreds in the column of Hundreds, and 2 Thousands at the left. Now we have taken the 8 Hundreds 3 times, the 7 Tens 3 times, and the 9 Ones 3 times. If we add these three Partial Products we shall have 3 times 879 for the final Product. First, we bring down the 7...