Difference between revisions of "2018 AMC 8 Problems/Problem 4"

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We count <math>3*3=9</math> unit squares in the middle, and <math>4</math> small triangles each with an area of <math>1</math>. Thus, the answer is <math>9+4=\boxed{\textbf{(C) } 13}</math>
 
We count <math>3*3=9</math> unit squares in the middle, and <math>4</math> small triangles each with an area of <math>1</math>. Thus, the answer is <math>9+4=\boxed{\textbf{(C) } 13}</math>
 
 
 
  
 
==See Also==
 
==See Also==
 
{{AMC8 box|year=2018|num-b=3|num-a=5}}
 
{{AMC8 box|year=2018|num-b=3|num-a=5}}
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Revision as of 16:52, 21 November 2018

Problem 4

The twelve-sided figure shown has been drawn on $1 \text{ cm}\times 1 \text{ cm}$ graph paper. What is the area of the figure in $\text{cm}^2$?

[asy] unitsize(8mm); for (int i=0; i<7; ++i) {   draw((i,0)--(i,7),gray);   draw((0,i+1)--(7,i+1),gray); } draw((1,3)--(2,4)--(2,5)--(3,6)--(4,5)--(5,5)--(6,4)--(5,3)--(5,2)--(4,1)--(3,2)--(2,2)--cycle,black+2bp); [/asy]

$\textbf{(A) } 12 \qquad \textbf{(B) } 12.5 \qquad \textbf{(C) } 13 \qquad \textbf{(D) } 13.5 \qquad \textbf{(E) } 14$

Solution

We count $3*3=9$ unit squares in the middle, and $4$ small triangles each with an area of $1$. Thus, the answer is $9+4=\boxed{\textbf{(C) } 13}$

See Also

2018 AMC 8 (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
All AJHSME/AMC 8 Problems and Solutions

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