Difference between revisions of "2014 AMC 10B Problems/Problem 7"

m (Solution)
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<math>100(\frac{A}{B}-1)=x</math>
 
<math>100(\frac{A}{B}-1)=x</math>
  
<math>\boxed{100(\frac{A-B}{B}) (\textbf{A})}=x</math>.
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<math>(\textbf{A}) \boxed{100(\frac{A-B}{B}) }=x</math>.
  
 
==See Also==
 
==See Also==
 
{{AMC10 box|year=2014|ab=B|num-b=6|num-a=8}}
 
{{AMC10 box|year=2014|ab=B|num-b=6|num-a=8}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 15:09, 8 June 2017

Problem

Suppose $A>B>0$ and A is $x$% greater than $B$. What is $x$?

$\textbf {(A) } 100(\frac{A-B}{B}) \qquad \textbf {(B) } 100(\frac{A+B}{B}) \qquad \textbf {(C) } 100(\frac{A+B}{A})\qquad \textbf {(D) } 100(\frac{A-B}{A}) \qquad \textbf {(E) } 100(\frac{A}{B})$

Solution

We have that A is $x\%$ greater than B, so $A=\frac{100+x}{100}(B)$. We solve for $x$. We get

$\frac{A}{B}=\frac{100+x}{100}$

$100\frac{A}{B}=100+x$

$100(\frac{A}{B}-1)=x$

$(\textbf{A}) \boxed{100(\frac{A-B}{B}) }=x$.

See Also

2014 AMC 10B (ProblemsAnswer KeyResources)
Preceded by
Problem 6
Followed by
Problem 8
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

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