Question

What is the missing length?

Answer 1

Answer:  13.722 km ;  or, write as:  13  13/18 km .
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Explanation:
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Area = Length * width ; 
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or, write as:  A = L * w ;
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Given: A = 247 km² ; 
           
          L = 18 km ; 
 
          w = "y" ; 
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 Find:  "y"
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  A = L * w ; 
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Plug in our values:
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  247 km² = 18 km * "y" ;  solve for "y" (in units of "km") ;

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        18 y = 247 ; 
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Divide each side of the equation by "18"; to isolate "y" on one side of the equation; and to solve for "y" :
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        18 y / 18 = 247 / 18 ;
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  to get:
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              y = 13.7222222222222222...... km ;  round to: 13.722 km

                   or;  y = 13  13/18 km .
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