Difference between revisions of "1981 AHSME Problems/Problem 4"

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==Problem==  
 
==Problem==  
If three times the larger of two numbers is four times the smaller and the difference between the numbers is <math>8</math>, the the larger of two numbers is:
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If three times the larger of two numbers is four times the smaller and the difference between the numbers is <math>8</math>, the the larger of two numbers is
  
<math>\text{(A)}\quad 16 \qquad \text{(B)}\quad 24 \qquad \text{(C)}\quad 32 \qquad  \text{(D)}\quad 44 \qquad \text{(E)} \quad 52 </math>
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<math>\text{(A)}\ 16 \qquad \text{(B)}\ 24 \qquad \text{(C)}\ 32 \qquad  \text{(D)}\ 44 \qquad \text{(E)} \ 52 </math>
  
 
==Solution==
 
==Solution==
Let the smaller number be <math>x</math> and the larger number be <math>y.</math> We can use the information given in the problem to write two equations:
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Let <math>x</math> be the smaller number and <math>y</math> be the larger number.  Then <math>3y = 4x</math>, so <math>x = \frac{3}{4}y</math>. Also, <math>y - x = 8</math>, so <math>y - \frac{3}{4}y = \frac{1}{4}y = 8</math>, and <math>y = \boxed{(\textbf{C})\ 32}</math>.
  
1) Three times the larger of two numbers is four times the smaller.
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==See also==
<cmath> 3y = 4x </cmath>
 
  
2) The difference between the number is <math>8</math>.
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{{AHSME box|year=1981|num-b=3|num-a=5}}
 
 
<cmath> y - x = 8 </cmath>
 
 
 
Solving this system of equation yields <math>x = 24</math> and <math>y = 32</math>. The answer is <math>\text{C}.</math>
 
 
 
{{AHSME box|year=1981|before=3|num-a=5}}
 
  
 
{{MAA Notice}}
 
{{MAA Notice}}

Latest revision as of 15:57, 18 August 2025

Problem

If three times the larger of two numbers is four times the smaller and the difference between the numbers is $8$, the the larger of two numbers is

$\text{(A)}\ 16 \qquad \text{(B)}\ 24 \qquad \text{(C)}\ 32 \qquad  \text{(D)}\ 44 \qquad \text{(E)} \ 52$

Solution

Let $x$ be the smaller number and $y$ be the larger number. Then $3y = 4x$, so $x = \frac{3}{4}y$. Also, $y - x = 8$, so $y - \frac{3}{4}y = \frac{1}{4}y = 8$, and $y = \boxed{(\textbf{C})\ 32}$.

See also

1981 AHSME (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 26 27 28 29 30
All AHSME Problems and Solutions


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