Difference between revisions of "1968 AHSME Problems/Problem 24"

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== See also ==
 
== See also ==
{{AHSME box|year=1968|num-b=23|num-a=25}}   
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{{AHSME 35p box|year=1968|num-b=23|num-a=25}}   
  
 
[[Category: Intermediate Algebra Problems]]
 
[[Category: Intermediate Algebra Problems]]
 
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{{MAA Notice}}

Latest revision as of 00:53, 16 August 2023

Problem

A painting $18$" X $24$" is to be placed into a wooden frame with the longer dimension vertical. The wood at the top and bottom is twice as wide as the wood on the sides. If the frame area equals that of the painting itself, the ratio of the smaller to the larger dimension of the framed painting is:

$\text{(A) } 1:3\quad \text{(B) } 1:2\quad \text{(C) } 2:3\quad \text{(D) } 3:4\quad \text{(E) } 1:1$


Solution

Let the width of the frame on the sides to be $x$.

Then, the width of the frame on the top and bottom is $2x$.

The area of the frame is then $x\cdot 2x-18\cdot24$

Setting the area of the frame equal to the area of the picture, \[(2x+18)(4x+24)-18\cdot24 = 18\cdot24\] Solving, \[8x^2+120x+432 = 864\] \[x^2+15x-54=0\] \[(x+18)(x-3)=0\Rightarrow x=3\]

Therefore, the ratio of the smaller side to the larger side is $\frac{18+2\cdot3}{24+4\cdot3}=\frac{24}{36}=\boxed{2:3 (C)}$.

~AOPS81619

See also

1968 AHSC (ProblemsAnswer KeyResources)
Preceded by
Problem 23
Followed by
Problem 25
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All AHSME Problems and Solutions

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