Difference between revisions of "1991 AHSME Problems/Problem 3"

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== Problem ==
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<math>(4^{-1}-3^{-1})^{-1}=</math>
 
<math>(4^{-1}-3^{-1})^{-1}=</math>
  
 
(A) <math>-12</math>  (B) <math>-1</math>  (C) <math>\frac{1}{12}</math>  (D) <math>1</math>  (E) <math>12</math>
 
(A) <math>-12</math>  (B) <math>-1</math>  (C) <math>\frac{1}{12}</math>  (D) <math>1</math>  (E) <math>12</math>
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== Solution ==
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<math>\fbox{A}</math> This is <math>\frac{1}{\frac{1}{4} - \frac{1}{3}} = \frac{1}{\frac{-1}{12}} = -12.</math>
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== See also ==
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{{AHSME box|year=1991|num-b=2|num-a=4}} 
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[[Category: Introductory Algebra Problems]]
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{{MAA Notice}}

Latest revision as of 17:14, 23 February 2018

Problem

$(4^{-1}-3^{-1})^{-1}=$

(A) $-12$ (B) $-1$ (C) $\frac{1}{12}$ (D) $1$ (E) $12$

Solution

$\fbox{A}$ This is $\frac{1}{\frac{1}{4} - \frac{1}{3}} = \frac{1}{\frac{-1}{12}} = -12.$

See also

1991 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 2
Followed by
Problem 4
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 26 27 28 29 30
All AHSME Problems and Solutions

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