Respuesta :

The answer is:  "25 feet
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Explanation:
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Perimeter  = 2*(length) + 2*(width); 

or;  "P = 2L + 2w " ;.
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In this case:  

"P = (2L + 2w) − 2 ⅚ " ; solve for "P" ; all units are in "feet (ft)" ;
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From the diagram; we are given:
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  L = 12 
¼ ;
 
  w = 10 ; 
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→   " P = { [2* (12 ¼) ] + [2* 10] }  − 2 ⅚  " ;  Solve for "P" ;
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Note:  Rewrite "12 
¼" ;  AND:  "2 ⅚" as "improper fractions" :
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→ " 12 ¼ = [ (4*12) + 1 ] / 4 = [tex] \frac{48+1}{4} [/tex] = [tex] \frac{49}{4}[/tex] "  ;

→ " 2 ⅚  = [ (6*2) + 5 ] / 6 = [tex] \frac{12+5}{6} [/tex] = [tex] \frac{17}{6}[/tex] "   ;
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Rewrite our equation: 

→   " P = { [2* (12 ¼) ] + [2* 10] }  − 2 ⅚  " ;;

substituting the "mixed numbers" with "improper fractions" ;
→   " P = { [2* ([tex] \frac{49}{4}[/tex]) + [2* 10] }  − [tex] \frac{17}{6}[/tex] " ;
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→ Note: " 2*[tex] \frac{49}{4}[/tex] ;

                   = [tex] \frac{2}{1} [/tex] *[tex] \frac{49}{4}[/tex] " ;

The "2" in the "  [tex] \frac{2}{1} [/tex]  " 
      cancels to "1" ; and the "4" in the " [tex] \frac{49}{4}[/tex] " 
     cancels to "2" ;  {Since:  "(4÷2=2)" ; and since:  "(2÷2=1)" ;

    →  and we have:   " 2*[tex] \frac{49}{4}[/tex] = "  [tex] \frac{49}{2} [/tex]   " .
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Note:  {2*10] = 20 .
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So; we can rewrite our equation as follows:
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→ " P =  [tex] \frac{49}{2}[/tex]  +  20 − [tex] \frac{17}{6}[/tex] " ;  
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Now, multiply the entire equation (both sides) by "6" ;
                                        to get rid of the fractions;
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→ 6*{P =  [tex] \frac{49}{2}[/tex]  +  20 − [tex] \frac{17}{6}[/tex] } ;
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to get:
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  → 6P = ([tex] \frac{6}{2}[/tex] *49)  +  20  −  (6*[tex] \frac{17}{6}[/tex]) ;

  → 6P = (3 * 49) + 20  −  ([tex] \frac{6}{6} [/tex] * 17) ;

             →  6P = ( 3 * 49) + 20  −  (1 * 17)  ;

             →  6P = ( 3 * 49) + 20  −  (1 * 17)  ;

             →  6P =  (147) + 20 − 17 ;

             →  6P = 147 + 20 − 17 ;

             →  6P  = (147 + 20) − 17 ;
 
             →  6P = 167 − 17 ;

             →  6P = 150 ;
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Now, divide EACH SIDE of the equation by "6" ; to isolate "P" on one side of the equation; and to solve for "P" (which is our answer, in units of "feet" (ft). ;
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             → 6P / 6  =  150 / 6 ;

to get:  →   P = 25 .
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The answer is:  "25 feet" .
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