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# Math Puzzle: Guess the Number! (off-topic)

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1213
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+495

*** This is supposed to be an off-topic post, but I can't figure out how to tag it as such, so please forgive me ***

I'm thinking of a number, X.

• If you multply X by 15, the result's digits are all the same.

• If you reverse the digits of X, the result is a prime number.

• The square of X minus the square of another number is equal to exactly 1200.

• If you take the entire period of the reciprocal of X, truncate it to a whole number, and take the reciprocal of the result, you should see something very familiar.

• If you put X in the following decimal point: " 1.X ", take the reciprocal, and round to 4 significant figures, then you may or may not have reversed the digits of X.

(I want to add, that I found all of these properties of "X" all by myself and did not find this anywhere or get it from any source. I'm not saying these properties have never been discovered, but I am saying this is all original, and it is pretty neat! Have fun guessing the number, and I hope it wasn't too easy‼)

What is X?

off-topic
Apr 10, 2016

#2
+495
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So it _was_ too easy.

Apr 10, 2016
edited by LambLamb  Apr 10, 2016

#1
+36928
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37 ?

Apr 10, 2016
#2
+495
+5

So it _was_ too easy.

LambLamb Apr 10, 2016
edited by LambLamb  Apr 10, 2016
#3
+776
+5

it was SO to EASY!

User101  Apr 11, 2016