Difference between revisions of "1950 AHSME Problems/Problem 1"

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<math> \textbf{(A)}\ 5\frac{1}{3}\qquad\textbf{(B)}\ 11\qquad\textbf{(C)}\ 10\frac{2}{3}\qquad\textbf{(D)}\ 5\qquad\textbf{(E)}\ \text{None of these answers} </math>
 
<math> \textbf{(A)}\ 5\frac{1}{3}\qquad\textbf{(B)}\ 11\qquad\textbf{(C)}\ 10\frac{2}{3}\qquad\textbf{(D)}\ 5\qquad\textbf{(E)}\ \text{None of these answers} </math>
  
==Solution==
+
==Solution 1==
 +
Given,
 +
The ratios are 2:4:6
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The number is 64
  
If the three numbers are in proportion to <math>2:4:6</math>, then they should also be in proportion to <math>1:2:3</math>. This implies that the three numbers can be expressed as <math>x</math>, <math>2x</math>, and <math>3x</math>. Add these values together to get:  
+
So, the sum of the ratios is 12
 +
 
 +
So, the first number is  <cmath>=\frac{64*2}{12}</cmath>=<cmath>\frac{32}{3}</cmath>
 +
So, the second number is <cmath>=\frac{64*4}{12}</cmath>=<cmath>\frac{64}{3}</cmath>
 +
 
 +
So, the third number is<cmath>=\frac{64*6}{12}</cmath>=32
 +
 
 +
We can see that the smallest is<cmath>=\frac{32}{3}</cmath>
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 +
<cmath>x=\frac{32}{3}=10 \frac{2}{3} </cmath>
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which is <math>\boxed{\textbf{(C)}}</math>.
 +
 
 +
 
 +
~Jayeed Mahmud (Bangladesh) 9/21/25
 +
 
 +
==Solution 2==
 +
 
 +
If the three numbers are in proportion to <math>2:4:6</math>, then they should also be in proportion to <math>1:2:3</math>. This implies that the three numbers can be expressed as <math>x</math>, <math>2x</math>, and <math>3x</math>. Add these values together to get:
 
<cmath>x+2x+3x=6x=64</cmath>
 
<cmath>x+2x+3x=6x=64</cmath>
 
Divide each side by 6 and get that  
 
Divide each side by 6 and get that  
<cmath>x=\frac{64}{6}=\frac{32}{3}=10 \frac{2}{3}</cmath>
+
<cmath>x=\frac{64}{6}=\frac{32}{3}=10 \frac{2}{3} </cmath>
which is answer choice <math>\boxed{\textbf{(C)}}</math>.
+
which is <math>\boxed{\textbf{(C)}}</math>.
  
 
==See Also==
 
==See Also==

Latest revision as of 11:07, 21 September 2025

Problem

If $64$ is divided into three parts proportional to $2$, $4$, and $6$, the smallest part is:

$\textbf{(A)}\ 5\frac{1}{3}\qquad\textbf{(B)}\ 11\qquad\textbf{(C)}\ 10\frac{2}{3}\qquad\textbf{(D)}\ 5\qquad\textbf{(E)}\ \text{None of these answers}$

Solution 1

Given, The ratios are 2:4:6 The number is 64

So, the sum of the ratios is 12

So, the first number is \[=\frac{64*2}{12}\]=\[\frac{32}{3}\] So, the second number is \[=\frac{64*4}{12}\]=\[\frac{64}{3}\]

So, the third number is\[=\frac{64*6}{12}\]=32

We can see that the smallest is\[=\frac{32}{3}\]

\[x=\frac{32}{3}=10 \frac{2}{3}\] which is $\boxed{\textbf{(C)}}$.


~Jayeed Mahmud (Bangladesh) 9/21/25

Solution 2

If the three numbers are in proportion to $2:4:6$, then they should also be in proportion to $1:2:3$. This implies that the three numbers can be expressed as $x$, $2x$, and $3x$. Add these values together to get: \[x+2x+3x=6x=64\] Divide each side by 6 and get that \[x=\frac{64}{6}=\frac{32}{3}=10 \frac{2}{3}\] which is $\boxed{\textbf{(C)}}$.

See Also

1950 AHSC (ProblemsAnswer KeyResources)
Preceded by
First Question
Followed by
Problem 2
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 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
All AHSME Problems and Solutions

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