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My Grandpa forwarded me a neat math trick which you should try:

1. Grab a calculator.
2. Key in the first three digits of your phone number (NOT the area code)
3. Multiply by 80
4. Add 1
5. Multiply by 250
6. Add the last 4 digits of your phone number
7. Add the last 4 digits of your phone number again
8. Subtract 250
9. Divide number by 2

The amazing result: Your entire phone number. This is a neat trick. But, being the ubergeek that I am, I had to figure out how it works.

First Step: Write out the instructions as a math equation. Let the first three digits of the phone number be ‘X’ and the last 4 digits be ‘Y’. The expected result will be 10000X + Y (your entire phone number).

[250(80X + 1) + 2Y - 250] / 2 = 10000X + Y

Next Step: Reduce the equation.

[20000X + 250 + 2Y - 250] / 2 = 10000X + Y

[20000X + 2Y] / 2 = 10000X + Y

10000X + Y = 10000X + Y

Final Step: It checks out, both sides are equivalent. Isn’t math fun!