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# 100

52 replies to this topic

### #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.
Pls visit New Puzzles section to see always fresh brain teasers.

Spoiler for Solution

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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

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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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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