Let "x" represent the "unknown number".
To write this as an equation:
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(⅔)x + 4 = 7 .
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To solve this equation (for "x") ;
Let us subtract "4" from EACH SIDE of the equation;
(⅔)x + 4 − 4 = 7 − 4 ;
to get:
(⅔)x = 3 ;
Now, multiple EACH SIDE of the equation by "3" (the denominator of the "fraction") ; to get rid of the "fraction" ;
3(⅔)x = 3*(3) ;
to get: 2x = 9 ;
Now, divide EACH SIDE of the equation by "2" ; to isolate "x" on one side of the equation; and to solve for "x" ;
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2x / 2 = 9 / 2
x = 9/2 = "4 ½ " ; or, write as: " 4.5" .
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