Difference between revisions of "2010 UNCO Math Contest II Problems/Problem 10"
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== Solution == | == Solution == | ||
+ | <math>\frac{n+2}{2}</math> if <math>n</math> is even; <math>\frac{n+1}{2}</math> if <math>n</math> is odd. | ||
== See also == | == See also == | ||
− | {{ | + | {{UNCO Math Contest box|year=2010|n=II|num-b=9|num-a=11}} |
[[Category:Intermediate Algebra Problems]] | [[Category:Intermediate Algebra Problems]] |
Latest revision as of 01:57, 13 January 2019
Problem
Let where
. What is the maximum number of elements in a subset
of
,
which has at least three elements, such that
for all
in
? As an example, the subset
of
has the property that the sum of any two elements is strictly bigger
than the third element, but the subset
does not since
is
greater than
.
Since there is no subset of size
satisfying these conditions, the answer for
is
.
Solution
if
is even;
if
is odd.
See also
2010 UNCO Math Contest II (Problems • Answer Key • Resources) | ||
Preceded by Problem 9 |
Followed by Problem 11 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 | ||
All UNCO Math Contest Problems and Solutions |