Lesson Tutor : ALGEBRA – Fun Things to Know

ALGEBRA – Fun Things to Know
By Elaine Ernst Schneider

1. 1. Did you know that if you multiply 111,111,111 X 111,111,111 that the answer is consecutive? Try it and then check the answer key to see what happens.

 

 

1. 1. Did you know that if you take your phone number through a series of algebraic steps in an equation, that you come out with the same phone number when you are done? Try it:

 

 

Take 60. Divide 60 by 2. Add your telephone number digits. Subtract 25. Multiply by 3. Subtract 15. Multiply by 2. Divide by 6. The answer is your telephone number. Check out the answer key to see this expressed in an equation.

1. Do you want to know a numerical magic trick? See if you can figure out this game:

Take a number, any number. Multiply by 2. Add 8. Divide by 2. Subtract the number you started with. Your answer is 4. What’s the trick? After you have thought about it for awhile, check out the answer key. But don’t cheat! Think first!

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Answer key:

1. 1. 111,111,111 X 111,111,111 = 12,345,678,987,654,321

 

 

Notice that the digits in the answer ascend consecutively until they reach nine and then descend consecutively from nine to one.

1. 1. Let x be your telephone number. Then set up the following equation:

 

 

2[3(60/2 + x-25) – 15]

6Solve what is within the parentheses first so that you have:

2[3(x + 5) – 15]

6Then solve what is in the brackets:

2 (3x + 15 –15)

6Continue to work the equation. Everything will cancel out except x (the telephone number).

1. The trick to this one is that you remember the number in the third step and divide by 2. In this example, the third step was to add 8, so the answer will be 4. If you add 10, the answer will be 5. Go ahead … amaze your friends!

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