Difference between revisions of "2002 AMC 10P Problems/Problem 2"

(See Also)
(Solution 1)
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== Solution 1 ==
 
== Solution 1 ==
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We can use the sum of an arithmetic series to solve this problem.
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Let the first integer equal a. The last integer in this string will be <math>a+10.</math> Plugging in <math>n=11, a_1=a,</math> and <math>a_n=a+10</math> into <math>\frac{n(a_1 + a_n)}{2}=2002,</math> we get:
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\begin{align*}
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\frac{11(a + a+10)}{2}&=2002 \\
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11(2a+10)&=4004 \\
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2a+10&=364 \\
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2a&=354 \\
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a&=177\\
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\end{align*}
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Thus, our answer is <math>\boxed{\textbf{(B) }177}</math>
  
 
== See Also ==
 
== See Also ==
 
{{AMC10 box|year=2002|ab=P|num-b=1|num-a=3}}
 
{{AMC10 box|year=2002|ab=P|num-b=1|num-a=3}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 06:58, 15 July 2024

Problem 2

The sum of eleven consecutive integers is $2002.$ What is the smallest of these integers?

$\text{(A) }175 \qquad \text{(B) }177 \qquad \text{(C) }179 \qquad \text{(D) }180 \qquad \text{(E) }181$

Solution 1

We can use the sum of an arithmetic series to solve this problem.

Let the first integer equal a. The last integer in this string will be $a+10.$ Plugging in $n=11, a_1=a,$ and $a_n=a+10$ into $\frac{n(a_1 + a_n)}{2}=2002,$ we get:

\begin{align*} \frac{11(a + a+10)}{2}&=2002 \\ 11(2a+10)&=4004 \\ 2a+10&=364 \\ 2a&=354 \\ a&=177\\ \end{align*}

Thus, our answer is $\boxed{\textbf{(B) }177}$

See Also

2002 AMC 10P (ProblemsAnswer KeyResources)
Preceded by
Problem 1
Followed by
Problem 3
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

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