Difference between revisions of "2001 AMC 10 Problems/Problem 5"

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== Solution ==
 
== Solution ==
  
Here is the picture: http://www.artofproblemsolving.com/Forum/download/file.php?id=6659&&mode=view
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[[File:Pentonimoes.gif]]
  
 
The ones with lines over the shapes have at least one line of symmetry. Counting the number of shapes that have line(s) on them,
 
The ones with lines over the shapes have at least one line of symmetry. Counting the number of shapes that have line(s) on them,

Revision as of 16:50, 1 January 2013

Problem

How many of the twelve pentominoes pictured below at least one line of symmetry?

$\textbf{(A)}\ 3 \qquad \textbf{(B)}\ 4 \qquad \textbf{(C)}\ 5 \qquad \textbf{(D)}\ 6 \qquad \textbf{(E)}\ 7$

Solution

Pentonimoes.gif

The ones with lines over the shapes have at least one line of symmetry. Counting the number of shapes that have line(s) on them, we find $\boxed{\textbf{(D)}\ 6}$ pentominoes.

See Also

2001 AMC 10 (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