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100


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#1 rookie1ja

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Posted 30 March 2007 - 07:02 PM

100 - Back to the Number Puzzles
Using four sevens (7) and a one (1) create the number 100. Except the five numerals you can use the usual mathematical operations (+, -, x, :), root and brackets ().

This old topic is locked since it was answered many times. You can check solution in the Spoiler below.
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#2 Rushingbrook

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Posted 01 June 2007 - 09:05 PM

Another solution would be
take 7-7=0
7-7=0
and put the one in front of it which would be100

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#3 larryhl

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Posted 05 June 2007 - 04:08 PM

concatenation isn't a mathematical operator ><
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#4 pranavojha

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Posted 08 June 2007 - 01:23 PM

How about this?

77+(7+7+7)+(7/7)+1

100=77+23
=77+(21)+(2)
=77+(7+7+7)+(1+1)
=77+(7+7+7)+((7/7)+1)


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#5 larryhl

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Posted 08 June 2007 - 02:27 PM

You're only allowed 4 sevens...not 7 sevens...
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#6 jarhead15

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Posted 21 June 2007 - 04:13 PM

uhh its just 7^2+7^2+1+1
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#7 larryhl

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Posted 21 June 2007 - 09:12 PM

uhh its just 7^2+7^2+1+1



That's two 7's, two 2's, and two 1's...not four 7's and one 1.
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#8 aesculapius

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Posted 24 June 2007 - 11:20 PM

it is 4 sevens just not 1 one. (7x7)=7^2.
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#9 davidhorton

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Posted 26 June 2007 - 03:45 AM

7 x (7+7) + cubed root of (7+1) = 100
7 X 14 + cubed root of 8
98 + 2 = 100
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#10 Daniel Camacho

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Posted 28 June 2007 - 10:56 PM

Hi all,
I thought of a unique solution...

By inverting 2 of the 4 - 7's

1 L7 L7

Ha Ha ! !
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