Difference between revisions of "2007 AMC 8 Problems/Problem 13"

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== Solution ==
 
== Solution ==
  
Let <math>x</math> be the number of elements in <math>A</math> and <math>B</math> which is equal.  
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Lets make x be the number of elements in A and B which is equal.  
  
 
Then we could form equation  
 
Then we could form equation  
<math>2x-1001 = 2007</math>
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2x-1001 = 2007
  
<math>2x = 3008</math>
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2x = 3008
  
<math>x = 1504</math>.
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x = 1504
  
The answer is <math>\boxed{\textbf{(C)}\ 1504}</math>
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The answer is C
  
 
==Video Solution by WhyMath==
 
==Video Solution by WhyMath==

Revision as of 19:17, 1 August 2021

Problem

Sets $A$ and $B$, shown in the Venn diagram, have the same number of elements. Their union has $2007$ elements and their intersection has $1001$ elements. Find the number of elements in $A$.

[asy] defaultpen(linewidth(0.7)); draw(Circle(origin, 5)); draw(Circle((5,0), 5)); label("$A$", (0,5), N); label("$B$", (5,5), N); label("$1001$", (2.5, -0.5), N);[/asy]

$\mathrm{(A)}\ 503 \qquad \mathrm{(B)}\ 1006 \qquad \mathrm{(C)}\ 1504 \qquad \mathrm{(D)}\ 1507 \qquad \mathrm{(E)}\ 1510$

Solution

Lets make x be the number of elements in A and B which is equal.

Then we could form equation 2x-1001 = 2007

2x = 3008

x = 1504

The answer is C

Video Solution by WhyMath

https://youtu.be/3LtGb3KjhoU

~savannahsolver

See Also

2007 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 12
Followed by
Problem 14
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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