Today's Math Problem

[StepBangin]

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
10. Do you recognize the answer?

[TomCollins]

1. Take the first three digits of your phone number.
2. Multiply it by 10,000.
3. Add the last 4 digits of your phone number.

Recognize it?

[madnak]

[ QUOTE ]
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
10. Do you recognize the answer?

[/ QUOTE ]

Add 1, multiply by 250, subtract 250. Add 1 and subtract 250 are redundant, so we can remove them. Multiply by 80, then multiply by 250, is the same as "multiply by 20,000." Now there's:

[ QUOTE ]
1. Key in the first three digits of your phone number (NOT the area code)
2. Multiply by 20000
3. Add 2 times the last 4 digits of your phone number
4. Divide number by 2
5. Do you recognize the answer?

[/ QUOTE ]

The whole thing is divided by 2, so we can cut the 20,000 in half as well as the term at step 3. So it's multiply by 10,000 then add the last 4 digits. Multiplying by 10,000 shifts the original three digits to the left by four, leaving 4 trailing zeroes. The last 4 digits of the phone number, when added, take the place of those trailing zeroes, leaving you with the complete phone number.

[sweetjazz]

1. Grab a calculator.
2. Pick your favorite number.
3. Add 0 to it.
4. Multiply it by 1.
5. Compute exp(ln(2)).
6. Add 7 to 3.
7. Aren't you glad you had your calculator.
8. Take your favorite number again. Look familiar?
9. You are now ready to seriously consider killing yourself.

[tomdemaine]

well isn't this just the fun forum /images/graemlins/smile.gif

[CallMeIshmael]

[ QUOTE ]
1. Grab a calculator.
2. Pick your favorite number.
3. Add 0 to it.
4. Multiply it by 1.
5. Compute exp(ln(2)).
6. Add 7 to 3.
7. Aren't you glad you had your calculator.
8. Take your favorite number again. Look familiar?
9. You are now ready to seriously consider killing yourself.

[/ QUOTE ]


I seriously "LOL"ed at this one