Difference between revisions of "1952 AHSME Problems/Problem 44"

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Let <math>n = 10a+b</math>. The problem states that <math>10a+b=k(a+b)</math>. We want to find <math>x</math>, where <math>10b+a=x(a+b)</math>. Adding these two equations gives <math>11(a+b) = (k+x)(a+b)</math>. Because <math>a+b \neq 0</math>, we have <math>11 = k + x</math>, or <math>x = \boxed{\textbf{(C) \ } 11-k}</math>.
 
Let <math>n = 10a+b</math>. The problem states that <math>10a+b=k(a+b)</math>. We want to find <math>x</math>, where <math>10b+a=x(a+b)</math>. Adding these two equations gives <math>11(a+b) = (k+x)(a+b)</math>. Because <math>a+b \neq 0</math>, we have <math>11 = k + x</math>, or <math>x = \boxed{\textbf{(C) \ } 11-k}</math>.
 
  
 
== See Also ==
 
== See Also ==
 
{{AHSME 50p box|year=1952|num-b=43|num-a=45}}
 
{{AHSME 50p box|year=1952|num-b=43|num-a=45}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 15:57, 24 December 2015

Problem

If an integer of two digits is $k$ times the sum of its digits, the number formed by interchanging the the digits is the sum of the digits multiplied by

$\textbf{(A) \ } 9-k  \qquad \textbf{(B) \ } 10-k \qquad \textbf{(C) \ } 11-k \qquad \textbf{(D) \ } k-1 \qquad \textbf{(E) \ } k+1$

Solution

Let $n = 10a+b$. The problem states that $10a+b=k(a+b)$. We want to find $x$, where $10b+a=x(a+b)$. Adding these two equations gives $11(a+b) = (k+x)(a+b)$. Because $a+b \neq 0$, we have $11 = k + x$, or $x = \boxed{\textbf{(C) \ } 11-k}$.

See Also

1952 AHSC (ProblemsAnswer KeyResources)
Preceded by
Problem 43
Followed by
Problem 45
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All AHSME Problems and Solutions

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