1. Grab a calculator. (you won't be able to do this one in your head)
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.
Do you recognize the answer?
3 comments:
I think it would have worked better if we had 7 digit phone numbers instead of 8 :)
Donna
Random Knits
((80x +1)250 + 2y - 250) / 2
= (250*80x + 250 +2y - 250) / 2
= 250*40x + y
= 10000x + y
= phone number
To work with 8 digit numbers, simply change the second instruction to key in the first four digits. (Or, for n-digit numbers, key in the first n-4 digits.
Worked for me too.
I luuuuuuuv mathematical problems.
Cathy
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