1991 AJHSME Problems/Problem 11: Difference between revisions
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Latest revision as of 23:07, 4 July 2013
Problem
There are several sets of three different numbers whose sum is
which can be chosen from
. How many of these sets contain a
?
Solution
Let the three-element set be
and suppose that
.
We need
and
. This gives us four solutions, so there are
sets with a
also with the desired properties
.
See Also
| 1991 AJHSME (Problems • Answer Key • Resources) | ||
| Preceded by Problem 10 |
Followed by Problem 12 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
| All AJHSME/AMC 8 Problems and Solutions | ||
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