Guest Posted January 28, 2009 Report Share Posted January 28, 2009 Using only four nines(9), make the number 100 in any form. You may use +, -, x, and /. Don't think too hard. This is a simple one. Reveal hidden contents 99 and 9/9 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 28, 2009 Report Share Posted January 28, 2009 Reveal hidden contents 99+9/9 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 28, 2009 Report Share Posted January 28, 2009 Reveal hidden contents 99 + (9/9=1)=> 99+1=100 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 28, 2009 Report Share Posted January 28, 2009 (edited) Kevin_3.1415 said: Using only four nines(9), make the number 100 in any form. You may use +, -, x, and /. Don't think too hard. This is a simple one. Reveal hidden contents 99+9/9=100 Edited January 28, 2009 by dhanu Quote Link to comment Share on other sites More sharing options...
0 Jiminy Cricket Posted January 28, 2009 Report Share Posted January 28, 2009 Kevin_3.1415 said: Using only four nines(9), make the number 100 in any form. You may use +, -, x, and /. Don't think too hard. This is a simple one. Reveal hidden contents 99+9/9=100 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 28, 2009 Report Share Posted January 28, 2009 The key was the clue to "keep it simple" Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 28, 2009 Report Share Posted January 28, 2009 Reveal hidden contents 9*9=81 81+9=90 90+9=99 99*9=891 891+9=900 900/9=100! I only used 7 9s! Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 28, 2009 Report Share Posted January 28, 2009 shellywelly0x said: Reveal hidden contents 9*9=81 81+9=90 90+9=99 99*9=891 891+9=900 900/9=100! I only used 7 9s! Nice try there is an easier way though. Quote Link to comment Share on other sites More sharing options...
0 bonanova Posted January 30, 2009 Report Share Posted January 30, 2009 Reveal hidden contents 99.99.... [borrowing the use of periods, of course ] Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 31, 2009 Report Share Posted January 31, 2009 bonanova said: Reveal hidden contents 99.99.... [borrowing the use of periods, of course ] Needs to be exactly 100. Quote Link to comment Share on other sites More sharing options...
0 peace*out Posted January 31, 2009 Report Share Posted January 31, 2009 Kevin_3.1415 said: Needs to be exactly 100. he's just having fun...let's see what i can do!! Reveal hidden contents 9+9+9+9+9+9+9+9+9+9+9+9+9/9. Reveal hidden contents 9*9+9/(9/9)+9+9/9 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 31, 2009 Report Share Posted January 31, 2009 Kevin_3.1415 said: Needs to be exactly 100. Technically, 99.99... (repeating) is equal to 100 in the real numbers system. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted February 1, 2009 Report Share Posted February 1, 2009 (edited) Reveal hidden contents I can do this with only 3 9s ((9/9)+9)=10 and 10 is 100 in the -1 power, a form of 100 Wait i found easier way, 99+9/9= 100!!!!!!!! Edited February 3, 2009 by bonanova spoiler added Quote Link to comment Share on other sites More sharing options...
0 Izzy Posted February 1, 2009 Report Share Posted February 1, 2009 Kevin_3.1415 said: Needs to be exactly 100. Actually, that does equal 100. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted February 3, 2009 Report Share Posted February 3, 2009 Izzy said: Actually, that does equal 100. only when rounded to the nearest hundredth Quote Link to comment Share on other sites More sharing options...
0 bonanova Posted February 3, 2009 Report Share Posted February 3, 2009 Kevin_3.1415 said: only when rounded to the nearest hundredth Actually, only when it's not rounded to the nearest anything. Consider: 1/3 = .33 .... That equality is true only when the 3's go on indefinitely. If they're truncated [terminated] after n decimal places, the equality fails. Now multiply both sides by 3: 1 = .99 .... Quote Link to comment Share on other sites More sharing options...
0 Guest Posted February 3, 2009 Report Share Posted February 3, 2009 bonanova said: Actually, only when it's not rounded to the nearest anything. Consider: 1/3 = .33 .... That equality is true only when the 3's go on indefinitely. If they're truncated [terminated] after n decimal places, the equality fails. Now multiply both sides by 3: 1 = .99 .... i am talking about 99.99 so it is different because i said four nines, but i like the thought Quote Link to comment Share on other sites More sharing options...
0 bonanova Posted February 3, 2009 Report Share Posted February 3, 2009 Kevin_3.1415 said: i am talking about 99.99 so it is different because i said four nines, but i like the thought 99.99 ... uses only four nines. And some periods, which in fairness the OP does not permit: only 9's and +, -, x, / Consider that "...." is a mathematical notation for infinite repetition. Thus any number, including two, 9's suffice to stand for an infinite number of 9's. 99.9 .... = 99.99 .... = 99.999 .... = 99.9999 .... = 100. Quote Link to comment Share on other sites More sharing options...
0 Prof. Templeton Posted February 3, 2009 Report Share Posted February 3, 2009 Reveal hidden contents 9/.9 x 9/.9 = 100 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted February 5, 2009 Report Share Posted February 5, 2009 Reveal hidden contents 99 + 9/9 = 100 Quote Link to comment Share on other sites More sharing options...
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Using only four nines(9), make the number 100 in any form. You may use +, -, x, and /.
Don't think too hard. This is a simple one.
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