APPENDIX A. Short Methods in Multiplication and Division. Art. 1. To multiply a number by 50: Multiply of the number by 100. Why? (a) Find the sum of the twelve products. (b) Find the sum of the twelve products. (c) Find the sum of the twelve products. Art. 4. To multiply a number by 49: Take 50 tin number, from which subtract the number itself. Why? (d) Find the sum of the twelve products. Art. 5. To multiply a number by 33: Multiply (e) Find the sum of the twelve products. Art. 9. To multiply a number by 25: Multiply of the number by 100. Why? (i) Find the sum of the twelve products. Art. 10. To multiply a number by 26: number, to which add the number itself. Take 25 times the Why? 900 + 36 = 936 (j) Find the sum of the twelve products. Art. 11. To multiply a number by 27: number, to which add twice the number. 36 × 27 25 times 36 = 900 Take 25 times the Why? 900+72972 (k) Find the sum of the twelve products. |