Thread: Try this algebra "trick"

hmm..that is pretty cool...I am a dork and I do like math tricks...anybody got a problem with that!

HEY HOW DID YOU KNOW MY PHONE NUMBER!

mine didn't work?

Edit...........it did. I added the individual numbers instead of the 4 digit number.

wow

DrChiro - Why do you think I posted it? Cause I'm a big dork too!!!

1-800-dial-a-stud, it works it works!

Thats wierd... But cool

Hey I see a potential way of getting some girls digits without asking directly.

They will catch on, once you ask them to reveal the final answer. Unless they are a bit clueless?

"I bet you I can get your number without you telling me."
Have them do steps 2 - 8 then ask them the answer write it down, tell them to clear the calculator or use your own divide by 2 and say "I got your number" or dial the number and watch as she jumps when her cell phone rings.

Will work great if you both have cell phones with calcs.

My algebra trick: Cheat off the person sitting next to you, finish course with a B+ on minimal effort.

jeje pritty cool bro ^^

Originally posted by I Are Baboon
My algebra trick: Cheat off the person sitting next to you, finish course with a B+ on minimal effort.

That's what I'm talking about

simple arithmetic!

Okay, let's take your first 3 digits...Let's say it's ABC. This number can be expressed as A-Hundreds plus B-tens plus C.

Okay, so this equals:
100A + 10B + C

When we multiple by 80 (Hmmm...I wonder where 80 came from, we'll see soon) we have:
8000A + 800B + 80C

Okay, Now we must add 1, so we have:
8000A + 800B + 80C + 1

Now we multiply by 250, so this leaves:
2000000A + 200000B + 20000C + 250
(You can now begin to see why 80 was chosen...nice round numbers that are 2 times multiples ot 10. Also, note the 250 term at the end.)

Okay, next we must add our last four digits. Let's say my last four digits are DEFG. This number is in the thousands and can be expressed as:
1000D + 100E + 10F +G

So, when we add it to what we were left with before, we have:
(2000000A + 200000B + 20000C + 250) + (1000D + 100E + 10F +G)

We add it again and now have:
(2000000A + 200000B + 20000C + 250) + (1000D + 100E + 10F +G) + (1000D + 100E + 10F +G)

This can be reduced to:
(2000000A + 200000B + 20000C + 250) + 2(1000D + 100E + 10F +G)

When we multiply through by our by two:
(2000000A + 200000B + 20000C + 250) + (2000D + 200E + 20F +2G)
(All the terms are now two times multiples of ten)

Anyway, now we subtract our 250(remember that) and the positive 250 term goes away:
(2000000A + 200000B + 20000C) + (2000D + 200E + 20F +2G)

All that's left is to divide by 2(imagine that), so we are left with:
(1000000A + 100000B + 10000C) + (1000D + 100E + 10F +G)

Voilla: Add the terms up and we have a number that looks like:

ABCDEFG

Yea that was an oldie but goodie.