Difference between revisions of "2024 AMC 10A Problems/Problem 21"

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==Solution==
 
==Solution==
|12 29 46 63 80|
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<cmath> \begin{bmatrix} 12 & 29 &46&63&80 \ 12&24&36&48&60\ 12&19&26&33&40\ 12&14&16&18&20\ 12&9&6&3&0\end{bmatrix}</cmath>
  
|12 24 36 48 60|
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-submitted by Astingo
 
 
|12 19 26 33 40|
 
 
 
|12 14 16 18 20|
 
 
 
|12  9  6  3  0|
 
 
 
submitted by Astingo
 

Revision as of 17:30, 8 November 2024

Problem

The numbers, in order, of each row and the numbers, in order, of each column of a $5 \times 5$ array of integers form an arithmetic progression of length $5{.}$ The numbers in positions $(5, 5), \,(2,4),\,(4,3),$ and $(3, 1)$ are $0, 48, 16,$ and $12{,}$ respectively. What number is in position $(1, 2)?$ \[\begin{bmatrix} . & ? &.&.&. \\ .&.&.&48&.\\ 12&.&.&.&.\\ .&.&16&.&.\\ .&.&.&.&0\end{bmatrix}\] $\textbf{(A) } 19 \qquad \textbf{(B) } 24 \qquad \textbf{(C) } 29 \qquad \textbf{(D) } 34 \qquad \textbf{(E) } 39$

Solution

\[\begin{bmatrix} 12 & 29 &46&63&80 \\ 12&24&36&48&60\\ 12&19&26&33&40\\ 12&14&16&18&20\\ 12&9&6&3&0\end{bmatrix}\]

-submitted by Astingo