Difference between revisions of "2007 iTest Problems/Problem 1"
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<math>(3,3+2)\equiv (3,5)</math>. <math>5</math> is a prime, so the answer is <math>\frac{3+5}{2}=4\Rightarrow \boxed{\mathrm{A}}</math>. | <math>(3,3+2)\equiv (3,5)</math>. <math>5</math> is a prime, so the answer is <math>\frac{3+5}{2}=4\Rightarrow \boxed{\mathrm{A}}</math>. | ||
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==See Also== | ==See Also== | ||
{{iTest box|year=2007|before=First Question|num-a=2}} | {{iTest box|year=2007|before=First Question|num-a=2}} | ||
[[Category:Introductory Number Theory Problems]] | [[Category:Introductory Number Theory Problems]] |
Revision as of 13:57, 24 February 2020
Problem
A twin prime pair is a set of two primes such that is greater than . What is the arithmetic mean of the two primes in the smallest twin prime pair?
Solution
We consider the first few primes. . isn't a prime, so this isn't a set of twin primes.
. is a prime, so the answer is .
See Also
2007 iTest (Problems, Answer Key) | ||
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Followed by: Problem 2 | |
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