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#1 2005-08-22 21:06:30

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,535

Two emailed Puzzles

A visitor has asked me by email:

I need a solution for the below questions:

Can you write 31 by usingly only digit 3 five times?

Can you place 10 coins in a five straight lines each having four coins?


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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#2 2005-08-22 22:38:24

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Two emailed Puzzles

Well, the second one is a star:

                            O

                O      O    O      O
           
                      O         O
                            O               
                    O              O

It would work if I could draw better, but you see what I mean.
The first one I'll have to think about.


Why did the vector cross the road?
It wanted to be normal.

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#3 2005-08-22 22:44:12

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,535

Re: Two emailed Puzzles

3^3 + 3 + 3/3 = 27 + 3 + 1 = 31

(That star would make a good logo !)


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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#4 2005-08-23 22:53:23

wcy
Member
Registered: 2005-08-04
Posts: 117

Re: Two emailed Puzzles

Another way:
33-3+3/3=33-3+1=31

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#5 2005-08-23 23:29:09

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Two emailed Puzzles

Technically, the answer to both is 'yes'.


Why did the vector cross the road?
It wanted to be normal.

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#6 2005-08-24 00:09:46

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,535

Re: Two emailed Puzzles

And I thought the answer to both was 31 ... silly me.


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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