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Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 12/AHSME
1997 AMC 12/AHSME
8
8
Part of
1997 AMC 12/AHSME
Problems
(1)
The Mientka Publishing Company
Source:
1/18/2009
Mientka Publishing Company prices its bestseller Where's Walter? as follows: C(n) \equal{} \begin{cases} 12n, &\text{if } 1 \le n \le 24\\ 11n, &\text{if } 25 \le n \le 48\\ 10n, &\text{if } 49 \le n \end{cases} where
n
n
n
is the number of books ordered, and
C
(
n
)
C(n)
C
(
n
)
is the cost in dollars of
n
n
n
books. Notice that
25
25
25
books cost less than
24
24
24
books. For how many values of
n
n
n
is it cheaper to buy more than
n
n
n
books than to buy exactly
n
n
n
books?
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8
<span class='latex-bold'>(A)</span>\ 3\qquad <span class='latex-bold'>(B)</span>\ 4\qquad <span class='latex-bold'>(C)</span>\ 5\qquad <span class='latex-bold'>(D)</span>\ 6\qquad <span class='latex-bold'>(E)</span>\ 8
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8
linear algebra
matrix