Difference between revisions of "2019 AMC 10A Problems/Problem 5"

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==Problem 5==
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{{duplicate|[[2019 AMC 10A Problems|2019 AMC 10A #5]] and [[2019 AMC 12A Problems|2019 AMC 12A #4]]}}
What is the greatest number of consecutive integers whose sum is <math>45 ?</math>
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==Problem==
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What is the greatest number of consecutive integers whose sum is <math>45?</math>
  
 
<math>\textbf{(A) } 9 \qquad\textbf{(B) } 25 \qquad\textbf{(C) } 45 \qquad\textbf{(D) } 90 \qquad\textbf{(E) } 120</math>
 
<math>\textbf{(A) } 9 \qquad\textbf{(B) } 25 \qquad\textbf{(C) } 45 \qquad\textbf{(D) } 90 \qquad\textbf{(E) } 120</math>
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==Solution==
 
==Solution==
 
Note that every term in the sequence <math>-44, -43..., 44, 45</math> cancels out except <math>45</math>. This results in <math>\boxed{\textbf{(D) } 90 }</math> integers.
 
Note that every term in the sequence <math>-44, -43..., 44, 45</math> cancels out except <math>45</math>. This results in <math>\boxed{\textbf{(D) } 90 }</math> integers.
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==See Also==
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{{AMC10 box|year=2019|ab=A|num-b=4|num-a=6}}
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{{AMC12 box|year=2019|ab=A|num-b=3|num-a=5}}
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{{MAA Notice}}

Revision as of 17:43, 9 February 2019

The following problem is from both the 2019 AMC 10A #5 and 2019 AMC 12A #4, so both problems redirect to this page.

Problem

What is the greatest number of consecutive integers whose sum is $45?$

$\textbf{(A) } 9 \qquad\textbf{(B) } 25 \qquad\textbf{(C) } 45 \qquad\textbf{(D) } 90 \qquad\textbf{(E) } 120$

Solution

Note that every term in the sequence $-44, -43..., 44, 45$ cancels out except $45$. This results in $\boxed{\textbf{(D) } 90 }$ integers.

See Also

2019 AMC 10A (ProblemsAnswer KeyResources)
Preceded by
Problem 4
Followed by
Problem 6
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 AMC 10 Problems and Solutions
2019 AMC 12A (ProblemsAnswer KeyResources)
Preceded by
Problem 3
Followed by
Problem 5
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 AMC 12 Problems and Solutions

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