Barry spent 1/5 of his month salary for rent and 1/8 of his monthly salary for his utility bill. if $1188 was left what was his month salary

The answer is:  " $ 1,760. " .

Explanation:


   x − (x/5) − (x/8) = 1188 ;  Solve for "x" (value in dollars) ; 

    To make matters easier, multiple the entire equation (both sides) by "40" ; 
   to get rid of the fractions:

              40 * {x − (x/5) − (x/8) = 1188 } ;

 to get:  → 40x − 8x − 5x = 1188 * 40 ;

             →  27x = 47520 ;  Divide EACH side of the equation by "27" ; 
to isolate "x" on one side of the equation; and to solve for "x" ;

             → 27x / 27 = 47520 / 27 ;  

to get:    →     x =  1760 dollars;  or,  " $ 1,760 " . 

To check our work, let us plug this value for "x" in the original equation, to see if the equation holds true:

x − (x/5) − (x/8) = 1188 ;

1760 − (1760/5) − (1760/8) =? 1188 ?

1760 − 352 − 220 = ? 1180 ?  Yes!  (check on calculator).