Difference between revisions of "1983 AHSME Problems/Problem 3"

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<math>\textbf{(A)}\ 2\qquad \textbf{(B)}\ 3\qquad \textbf{(C)}\ 7\qquad \textbf{(D)}\ 13\qquad \textbf{(E)}\ 17</math>
 
<math>\textbf{(A)}\ 2\qquad \textbf{(B)}\ 3\qquad \textbf{(C)}\ 7\qquad \textbf{(D)}\ 13\qquad \textbf{(E)}\ 17</math>
 
==Solution==
 
==Solution==
We are given that <math>p,q</math> and <math>r</math> are primes. In order to sum two another prime, either <math>p</math> or <math>q</math> has to be even, because the sum of an odd and an even is odd. The only odd prime is <math>2</math>, and it is also the smallest prime, so therefore, the answer is <math>\fbox{\textbf{(A)}2}</math>
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We are given that <math>p,q</math> and <math>r</math> are primes. In order to sum two another prime, either <math>p</math> or <math>q</math> has to be even, because the sum of an odd and an even is odd. The only odd prime is <math>2</math>, and it is also the smallest prime, so therefore, the answer is <math>\fbox{\textbf{(A)}2}</math>.
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==See Also==
 
==See Also==
 
{{AHSME box|year=1983|num-b=3|num-a=4}}
 
{{AHSME box|year=1983|num-b=3|num-a=4}}
  
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 07:19, 18 May 2016

Problem 3

Three primes $p,q$, and $r$ satisfy $p+q = r$ and $1 < p < q$. Then $p$ equals

$\textbf{(A)}\ 2\qquad \textbf{(B)}\ 3\qquad \textbf{(C)}\ 7\qquad \textbf{(D)}\ 13\qquad \textbf{(E)}\ 17$

Solution

We are given that $p,q$ and $r$ are primes. In order to sum two another prime, either $p$ or $q$ has to be even, because the sum of an odd and an even is odd. The only odd prime is $2$, and it is also the smallest prime, so therefore, the answer is $\fbox{\textbf{(A)}2}$.

See Also

1983 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 3
Followed by
Problem 4
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 26 27 28 29 30
All AHSME Problems and Solutions


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