Difference between revisions of "2007 iTest Problems/Problem 3"
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<math>28\Rightarrow 1+2+4+7+14=28\not>28</math> | <math>28\Rightarrow 1+2+4+7+14=28\not>28</math> | ||
| − | <math>56\Rightarrow 1+2+7+8+14+28=60>56</math> | + | <math>56\Rightarrow 1+2+4+7+8+14+28=60>56</math> |
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| + | Thus, <math>56\Rightarrow \boxed{\mathrm{C}}</math> is the answer. | ||
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==See Also== | ==See Also== | ||
{{iTest box|year=2007|num-b=2|num-a=4}} | {{iTest box|year=2007|num-b=2|num-a=4}} | ||
[[Category:Introductory Number Theory Problems]] | [[Category:Introductory Number Theory Problems]] | ||
Revision as of 19:58, 23 May 2008
Problem
An abundant number is a natural number that's proper divisors' sum is greater than the number. Which one of the following natural numbers is an abundant number?
Solution
Thus, 
is the answer.
See Also
| 2007 iTest (Problems, Answer Key) | ||
| Preceded by: Problem 2 |
Followed by: Problem 4 | |
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