Difference between revisions of "2006 AMC 10B Problems/Problem 5"

m (Solution 2)
m (Solution 2)
 
(One intermediate revision by the same user not shown)
Line 12: Line 12:
  
 
== Solution 2 ==
 
== Solution 2 ==
The area of a <math>2\times3</math> rectangle and a <math>3\times4</math> rectangle combined is <math>18</math>, so a <math>4\times4</math> square is impossible without overlapping. Thus, the next smallest square is a <math>5\times5</math>, which works, so the answer is B.
+
The area of a <math>2\times3</math> rectangle and a <math>3\times4</math> rectangle combined is <math>18</math>, so a <math>4\times4</math> square is impossible without overlapping. Thus, the next smallest square is a <math>5\times5</math>, which works, so the answer is <math>\boxed{B)25}</math>.
  
Note: If you do this, always check to see if it fits, because this doesn't always work. For example, a 3x3 and a 3x4 doesn't fit into a 5x5, even though their combined area is 21.
+
Note: If you do this, always check to see if it fits, because this doesn't always work. For example, a <math>3\times3</math> and a <math>3\times4</math> doesn't fit into a <math>5\times5</math>, even though their combined area is <math>21</math>.
  
 
== See Also ==
 
== See Also ==

Latest revision as of 21:51, 7 December 2024

Problem

A $2 \times 3$ rectangle and a $3 \times 4$ rectangle are contained within a square without overlapping at any point, and the sides of the square are parallel to the sides of the two given rectangles. What is the smallest possible area of the square?

$\textbf{(A) } 16\qquad \textbf{(B) } 25\qquad \textbf{(C) } 36\qquad \textbf{(D) } 49\qquad \textbf{(E) } 64$

Solution 1

By placing the $2 \times 3$ rectangle adjacent to the $3 \times 4$ rectangle with the 3 side of the $2 \times 3$ rectangle next to the 4 side of the $3 \times 4$ rectangle, we get a figure that can be completely enclosed in a square with a side length of 5. The area of this square is $5^2 = 25$.

Since placing the two rectangles inside a $4 \times 4$ square must result in overlap, the smallest possible area of the square is $25$.

So the answer is $\boxed{\textbf{(B) }25}$.

Solution 2

The area of a $2\times3$ rectangle and a $3\times4$ rectangle combined is $18$, so a $4\times4$ square is impossible without overlapping. Thus, the next smallest square is a $5\times5$, which works, so the answer is $\boxed{B)25}$.

Note: If you do this, always check to see if it fits, because this doesn't always work. For example, a $3\times3$ and a $3\times4$ doesn't fit into a $5\times5$, even though their combined area is $21$.

See Also

2006 AMC 10B (ProblemsAnswer KeyResources)
Preceded by
Problem 4
Followed by
Problem 6
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
All AMC 10 Problems and Solutions

The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions. AMC logo.png