strange math

[Micah]

Can you figure this out???
1. Key into the calculator the first 3 digits of your phone number (not
area code)
2. Multiply by 80
3. Add 1
4. Multiply by 250
5. Add last 4 digits of your phone number
6. Add last 4 digits of your phone number again
7. Subtract 250
8. Lastly, divide by 2
Is this your phone number?
If you can figure this out, please explain how the arithmetic works


I know we have some smart people on here, and I realize that the math cancels itself out, but it's still bugging me. Anyone wanna try and break it down into a few simple sentances?

 

[RoTi speed]

crazy s***.... Math is freaky!

 

[PaulMP3]

yep. got my #

 

[2K3 MSP]

That is pretty wierd...my house and my cell number both start with zero's for the 4-digit part, but it still worked...That's what i dont get...

 

[#878MSPChick]

Got my number too. That is some freaky s***.

 

[mazdadan]

Yeah worked for me too

 

[PatrickP5]

It's not that tough. I just worked it out in about 15 seconds - it's going to take longer to type it out than it did to figure it out:

Phone number = X1-X2
(X1 = first three numbers, X2 = last 4... that's not a minus - it's a dash)

[(80*X1+1)(250)+X2+X2-250]/2 = 125(80*X1+1)+X2-125

= 10000*X1 + 125 + X2 - 125 = 10000*X1+X2 = X1e4 + X2

the 10,000 moves the X1 over four spaces so it looks like: XXX0000, then add the X2 on to finish your number.

See? It's not so crazy tough. It's simple 6th-7th grade algebra. I can make up more for you if you want. I could make it so it works for your whole 10-digit number, whatever.


Patrick

 

[Little Beavis]

Can you figure this out???
1. Key into the calculator the first 3 digits of your phone number (not
area code)
2. Multiply by 80
3. Add 1
4. Multiply by 250
5. Add last 4 digits of your phone number
6. Add last 4 digits of your phone number again
7. Subtract 250
8. Lastly, divide by 2
Is this your phone number?
If you can figure this out, please explain how the arithmetic works

I know we have some smart people on here, and I realize that the math cancels itself out, but it's still bugging me. Anyone wanna try and break it down into a few simple sentances?

Consider the first three digits to be "X".
Consider the last four digits to be "Y"

Step 1 = first three digits = X
Step 2 = multiply by 80 = 80X
Step 3 = add 1 = 80X+1
Step 4 = multiply by 250 = 250*(80X+1) = 20000X + 250
Step 5 = add last four digits = 20000X + 250 + Y
Step 6 = add last four digits again = 20000X + 250 + 2Y
Step 7 = subtract 250 = 20000X + 2Y
Step 8 = Divide by 2 = 10000X + Y

The 10000 simply adds four zeros behind the first three digits and then adds the last four digits. . .Voila! Your phone number!

 

[Little Beavis]

s*** took me too long to type that and Patrick beat me to the punch!

Now if someone can tell me how this one is done. . .
http://www.digicc.com/fido/

 

[Roywhitep5]

wow that reminds me of when my friend found a way to get around the internet block on yahoo pool that we had at school.

click here, click on that, delete that part, type in pool, press enter, delete this blah blah blah and voila yahoo pool

the moral of the story is that whoever made this up needs a ps2

 

[StarvingRussian]

cool

 

[PatrickP5]

Now if someone can tell me how this one is done. . .
http://www.digicc.com/fido/

I think it's because you want to drink 7-Up.

 

[johnsharpe]

It's a math problem that has one outcome with variable inputs.

There is a solution to every math problem...you just need to know how to solve it. It's like those David Copperfield TV specials where he puts 8-10 icons in a circle on the screen and asks the TV audience to count around the circle randomly, while he removes specific icons. He always finds which one you're on, no matter how you work it.