This is crazy!

Amazing Math Problem of the Day:

Here is a math trick that is pretty amazing!
Grab a calculator. (You won't be able to do this one in your head!)
1. Key in the first three digits of your phone number (NOT the Area code)
2. Multiply by 80
3. Add 1
4. Multiply by 250
5. Add the last 4 digits of your phone number
6. Add the last 4 digits of your phone number again.
7. Subtract 250
8. Divide number by 2

Do you recognize the answer??