The correct answer is: 
[C]:  " 

" .
____________________________________________________Step-by-step explanation:____________________________________________________Given:
____________________________________________________  2 / (9x) = 4 / 7 ; solve for "x" ;
____________________________________________________Cross-multiply:
 → (9x)*4 = 2 * 7 ; 
 → 36x = 14 ; 
Divide each side of the equation by "36" ; 
 to isolate "x" on one side of the equation; & to solve for "x" ; 
 → 36x / 36 = 14 / 36 ; 
 x = 14/ 36 ; 
 → x = 14/36 = (14÷2) / (36÷2) = 7/18 ; 
______________________________________________________
The answer is: "
 

" ;
 → which is: 
Answer choice: [C]:  " 

" .
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