Difference between revisions of "2011 AMC 8 Problems/Problem 17"

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==Problem==
 
Let <math>w</math>, <math>x</math>, <math>y</math>, and <math>z</math> be whole numbers. If <math>2^w \cdot 3^x \cdot 5^y \cdot 7^z = 588</math>, then what does <math>2w + 3x + 5y + 7z</math> equal?
 
Let <math>w</math>, <math>x</math>, <math>y</math>, and <math>z</math> be whole numbers. If <math>2^w \cdot 3^x \cdot 5^y \cdot 7^z = 588</math>, then what does <math>2w + 3x + 5y + 7z</math> equal?
  
<math> \text{(A) } 21\qquad\text{(B) }25\qquad\text{(C) }27\qquad\text{(D) }35\qquad\text{(E) }56 </math>
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<math> \textbf{(A) } 21\qquad\textbf{(B) }25\qquad\textbf{(C) }27\qquad\textbf{(D) }35\qquad\textbf{(E) }56 </math>
  
 
==Solution==
 
==Solution==
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The [[prime factorization]] of <math>588</math> is <math>2^2\cdot3\cdot7^2.</math> We can see <math>w=2, x=1,</math> and <math>z=2.</math> Because <math>5^0=1, y=0.</math>
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<cmath>2w+3x+5y+7z=4+3+0+14=\boxed{\textbf{(A)}\ 21}</cmath>
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==Video Solution==
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https://youtu.be/PxBKpg-HKu8  ~David
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==Video Solution 2==
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https://youtu.be/5vpKkAue8Is. Soo, DRMS, NM
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==Video Solution 3==
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https://youtu.be/_4KL96b9vbY
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~savannahsolver
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==Video Solution 4 by SpreadTheMathLove==
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https://www.youtube.com/watch?v=mYn6tNxrWBU
  
 
==See Also==
 
==See Also==
 
{{AMC8 box|year=2011|num-b=16|num-a=18}}
 
{{AMC8 box|year=2011|num-b=16|num-a=18}}
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{{MAA Notice}}

Latest revision as of 14:08, 17 December 2023

Problem

Let $w$, $x$, $y$, and $z$ be whole numbers. If $2^w \cdot 3^x \cdot 5^y \cdot 7^z = 588$, then what does $2w + 3x + 5y + 7z$ equal?

$\textbf{(A) } 21\qquad\textbf{(B) }25\qquad\textbf{(C) }27\qquad\textbf{(D) }35\qquad\textbf{(E) }56$

Solution

The prime factorization of $588$ is $2^2\cdot3\cdot7^2.$ We can see $w=2, x=1,$ and $z=2.$ Because $5^0=1, y=0.$

\[2w+3x+5y+7z=4+3+0+14=\boxed{\textbf{(A)}\ 21}\]

Video Solution

https://youtu.be/PxBKpg-HKu8 ~David

Video Solution 2

https://youtu.be/5vpKkAue8Is. Soo, DRMS, NM

Video Solution 3

https://youtu.be/_4KL96b9vbY

~savannahsolver

Video Solution 4 by SpreadTheMathLove

https://www.youtube.com/watch?v=mYn6tNxrWBU

See Also

2011 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 16
Followed by
Problem 18
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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