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Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 12/AHSME
1962 AMC 12/AHSME
27
27
Part of
1962 AMC 12/AHSME
Problems
(1)
Binary Operator
Source:
3/3/2010
Let
a
@
b
a @ b
a
@
b
represent the operation on two numbers,
a
a
a
and
b
b
b
, which selects the larger of the two numbers, with a@a \equal{} a. Let
a
!
b
a ! b
a
!
b
represent the operator which selects the smaller of the two numbers, with a ! a \equal{} a. Which of the following three rules is (are) correct?
(1)
\ a@b \equal{} b@a \qquad
(2)
\ a@(b@c) \equal{} (a@b)@c \qquad
(3)
\ a ! (b@c) \equal{} (a ! b) @ (a ! c)
<
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(
A
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(
1
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only
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(
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only
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(
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(1) and (2) only
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(
D
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(1) and (3) only
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(
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all three
<span class='latex-bold'>(A)</span>\ (1)\text{ only} \qquad <span class='latex-bold'>(B)</span>\ (2) \text{ only} \qquad <span class='latex-bold'>(C)</span>\ \text{(1) and (2) only} \qquad <span class='latex-bold'>(D)</span>\ \text{(1) and (3) only} \qquad <span class='latex-bold'>(E)</span>\ \text{all three}
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(
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(
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only
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(1) and (2) only
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(
D
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(1) and (3) only
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(
E
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all three