Arithmetic, Algebra, Mathemagic
Arithmetic can be called the study of "known" numbers, or calculation. Algebra, then, is the study of "unknown" numbers. Arithmetic is easy. All it takes is a good teacher, and sufficient practice. Likewise , since all real numbers (whether known or unknown) obey the same rules, algebra is easy – provided the student is well taught and well practiced. Knowing simple algebra empowers one to do some pretty interesting and impressive things, including all kinds of " mathemagic " tricks, like the one below (involving just basic algebra). Give it a try! Here goes: 1. Start with the number of doors in your home. 2. Multiply by 2. 3. Add 5. 4. Multiply by 50. 5. Add the number of legs on a normal moose. 6. Subtract 335. 7. If you’ ve already had your birthday this year, add this year; otherwise, add last year. 8. subtract the number of days in July. 9. Add 85. 10. Subtract the year you were born. 11. Add 29. 12. Subtract the ...