Difference between revisions of "2014 AMC 10B Problems/Problem 2"

(Solution 2)
(Solution 2)
Line 8: Line 8:
 
<cmath>\frac{2^3+2^3}{2^{-3}+2^{-3}}\\=\frac{2^6+2^6}{1+1}\\={2^6}. </cmath>
 
<cmath>\frac{2^3+2^3}{2^{-3}+2^{-3}}\\=\frac{2^6+2^6}{1+1}\\={2^6}. </cmath>
 
Hence, the fraction equals to <math>\boxed{{64 (\textbf{E})}}</math>.
 
Hence, the fraction equals to <math>\boxed{{64 (\textbf{E})}}</math>.
 
==Solution 2==
 
We could also do quick math\, solving the exponents to get:
 
<cmath>\frac{8+8}{</cmath>\frac{1}{8}<cmath>+</cmath>\frac{1}{8}<cmath>}\\=\frac{2^6+2^6}{1+1}\\={2^6}. </cmath>
 
  
 
==See Also==
 
==See Also==
 
{{AMC10 box|year=2014|ab=B|num-b=1|num-a=3}}
 
{{AMC10 box|year=2014|ab=B|num-b=1|num-a=3}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 13:47, 24 July 2018

Problem

What is $\frac{2^3 + 2^3}{2^{-3} + 2^{-3}}$?

$\textbf {(A) } 16 \qquad \textbf {(B) } 24 \qquad \textbf {(C) } 32 \qquad \textbf {(D) } 48 \qquad \textbf {(E) } 64$

Solution

We can synchronously multiply ${2^3}$ to the polynomials both above and below the fraction bar. Thus, \[\frac{2^3+2^3}{2^{-3}+2^{-3}}\\=\frac{2^6+2^6}{1+1}\\={2^6}.\] Hence, the fraction equals to $\boxed{{64 (\textbf{E})}}$.

See Also

2014 AMC 10B (ProblemsAnswer KeyResources)
Preceded by
Problem 1
Followed by
Problem 3
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All AMC 10 Problems and Solutions

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