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**3.**Numeral system which uses 0-9 and A-F**9.**Six-sided polygon**12.**Numbers 2,13,57 are all ________**13.**Greek letter used to represent a sum in a series**15.**repeated exponentiation**16.**Platonic solid with the most (20) faces**18.**Simplest platonic solid, also known as a triangular pyramid**23.**Statement thought to be true but which proof is not yet known**25.**2π**26.**Symbol used for the roots of numbers**28.**The square root of -1 is ______**29.**The Pythagoreans believed that all even numbers are _______**30.**Arabic numbers were invented in _______

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**1.**The Abel-Ruffini theorem states a formula for solving _______ functions cannot exist**2.**Self-contradictory statement**4.**Founder of set theory**5.**This polygon cannot be constructed with a compass and a ruler**6.**Ten to the power of hundred**7.**The ______ conjecture is the only Millenium Prize Problem solved so far. It was solved in 2003 by Grigori Perelman, who later declined the $1,000,000 prize money.**8.**Famous philosopher, who invented the convention of representing unknowns in equations by x and y**10.**By gluing together two sides of a tape you get a one sided surface named the _______ strip**11.**This number has no roman numeral representation**14.**In _____ arithmetic numbers "wrap around" when reaching a certain value. It is often called clock arithmetic.**17.**Statement assumed to be true**19.**Field of mathematics in which a donut and a cup are considered equal**20.**The plus sign (+) originally stood for this Latin word**21.**Less than zero**22.**Written at the end of a proof**24.**Earliest known mathematician**27.**Lemniscate is the shape of what mathematical symbol?**29.**Number of colours required to colour any map so that no adjacent regions have the same colour