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Chelsey

Senior member
Dec 18, 2003
534
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First person that gets these correct gets a :cookie:

First one:
Totally odd
When we multiply multidigit numbers, we have to do some addition as well - the final step is to sum the subtotals. Here's a puzzle that exposes the steps and tags the various digits as odd ("O") or even ("E"):

EEO
X OO
---------
EOEO
+ EEO
----------
OOOOO

Find the numbers that satisfy this scheme.

The algebra of cooperation
Solve the number rebus
USA+USSR = PEACE
The same letters stand for the same digits, different letters denote different digits.

Restore the Product
The figure shows a product in which some of the figures are rubbed out and replaced by asterisks. Restore the absent figures.

*1*
X 3*2
--------
*3*
3*2*
*2*5
--------
****3*

Mirror Numbers
Two numbers are called mirror numbers if one is obtained from the other by reversing the order of digits--for example, 123 and 321. Find two mirror numbers whose product is 92,565.

There are a few more, if I can figure out how to make the graphics then I will post them as well. Thanks in advance for your answers!
 
C

Chelsey

Senior member
Dec 18, 2003
534
0
0
Good job boys, now try for Totally Odd, The Algebra of Cooperation, and Restore the Product :D
 
Kyteland

Kyteland

Diamond Member
Dec 30, 2002
5,747
1
81
u: 4 s: 8 a: 3 e: 5 c: 6 r: 2 p: 0 483+4882=05365
u: 8 s: 6 a: 5 e: 9 c: 2 r: 4 p: 0 865+8664=09529
u: 8 s: 7 a: 6 e: 9 c: 4 r: 3 p: 0 876+8773=09649
u: 9 s: 3 a: 2 e: 0 c: 7 r: 8 p: 1 932+9338=10270

I'm just too slow for chuckywang here....
 
Kyteland

Kyteland

Diamond Member
Dec 30, 2002
5,747
1
81
Originally posted by: chuckywang
Originally posted by: Kyteland
287*39=11193

681*17=11577

861*13=11193
Click to expand...

Nice, i was just about to post 861*13
Click to expand...

That's the great thing about a brute force c++ program. It checks everything. I had to revise my answer twice because of a bug though.

You must have had a 5 min head start on the other problems. You kept getting them faster than me.

Yeah, that's the ticket, a head start. :shiftyeyes;
 
C

Chelsey

Senior member
Dec 18, 2003
534
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0
Ok guys, I've only got one left, and that's the Totally odd one. Someone's gotta be able to figure it out!
 
TuxDave

TuxDave

Lifer
Oct 8, 2002
10,571
3
71
Originally posted by: Chelsey
Ok guys, I've only got one left, and that's the Totally odd one. Someone's gotta be able to figure it out!
Click to expand...

How can an odd + odd = odd? (in the ones digit of the summation) There's something wrong with your formatting or the original problem.

EOEO
XEEO (x is a spacer)

EOEO
EEO

Both scenarios cannot equal OOOOO. The first you cannot get an odd+odd = odd in the ones digit.

The second is that in order to get E+E = OO in the thousands digit, you need a carry of 1 from the addition of O+E in the hundreds digit. If O+E carries a 1, the O+E from the tens digit will carry a 1 and then the hundreds digit cannot be O.
 
C

Chelsey

Senior member
Dec 18, 2003
534
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0
I just checked the Totally Odd problem again, and it's still even + even = even, odd + odd = odd.
 
DrPizza

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,601
167
111
www.slatebrookfarm.com
before you get to the odd + odd = odd in the even odd problem,

note that the algorithm being used isn't one where you use 0 as a placeholder...
the +EEO on the 4th line is shifted over by the + sign.

(otherwise, how can you multiply the original 3 digit number by a certain number of 10's and get a number less than 1000?)

It should read
EOEO
+EEO0

look carefully, there's a zero there. (Using the most common algorithm used for grade school multiplication in the U.S.)
 
A

amoeba

Diamond Member
Aug 7, 2003
3,162
1
0
for some reason I thought this thread said Brain Taser.

I was like sweet jesus that would hurt.
 
DrPizza

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,601
167
111
www.slatebrookfarm.com
I gave it a quick shot... I'm not writing any code to figure it out, or trying any harder

close but no cigar:
881
*17
-------
6167
881
--------
14977

That should at least give the idea... the 4 ruins it, but that's what the problem means.
 
C

Chelsey

Senior member
Dec 18, 2003
534
0
0
Bump

This is due soon guys :p I think it's the way my teacher wrote it, you're probably right about the zero. So, let's assume that it's what Dr. Pizza said, EOEO
+EEO0
 
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