Brain Teasers
Six Nines
Without introducing "+" signs, arrange six "9's" in such a way that they add up to 100.
Answer
(999-99)/9 = 900/9 = 100(99 -(-9/9))* 9/9= (99 -(-1)) * 1 = 100
99 99/99
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Query do they 'add' up to 100 or compute to 100
Yes - without a doubt the wording is incorrect, nevertheless: the 'intent' was clear enough.. The answer was fairly obvious. I would ask the reader to arrange the nines into an equation of integers that results in 100 without using addition.
can you repeat that?
TUT TUT!!!!!!!
is it just me or does sillywilly feel the need to express his "superior acheivement in langular excelence"
No, it's not just you, i have also noticed this about silly. I have even commented to him that I hope he does not teach math, as it is people like him who put ordinary folks off by making it sound more complex than it is. Silly has denied this and asked what I mean!!!
The second answer seems kind of cheap -- you can't use a plus sig, but a double negative is okay?
yeah, using double negative is just the same as using a + sign. anyway, i got the first answer.
I got 99 99/99, but then I went further:
9 9/9 * 9 9/9 = 100
9*9/(.9*.9)^(9/9) = 100
(9/0.9)^(SQRT(SQRT(9*9))-9/9) = 100
(9-SQRT(9))!/(SQRT(9)*SQRT(9)-.9-.9) = 100
Lots more.
9 9/9 * 9 9/9 = 100
9*9/(.9*.9)^(9/9) = 100
(9/0.9)^(SQRT(SQRT(9*9))-9/9) = 100
(9-SQRT(9))!/(SQRT(9)*SQRT(9)-.9-.9) = 100
Lots more.
A grade C puzzle. It doesn't have a unique answer. 99 99/99 involves a tacit '+ because it is read, "ninety-nine-AND-ninety-nine-ninety-ninths". For the same reason, I was a little uneasy with my first thoughts: 99.9999 with a bar over the decimal to indicate a repeating '9' and equal 100.
Or:
99-(-99/99)
99-(-99/99)
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