Question 1134874
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<pre>
    S + C = 66750      (1)   (for the <U>S</U>tore and <U>C</U>ollege)

    S = 3*C + 1150     (2)


You can rewrite these two equations in standard form


    S +   C = 66750    (1) 

    S - 3*C =  1150    (2)


Now subtract equation (1) from equation (2). You will get


        -4*c = 1150 - 66750,   or

         4C = 66750 - 1150

         4C = 65600  ==============>  C = 65600/4 = 16400.


<U>ANSWER</U>.  The earning for the college is  $16400.  The rest  66750 - 16400 = 50350  dollars is the earning for the store.


<U>CHECK</U>.   3*C + 1150 = 3*16400 + 1150 = 50350.    ! Precisely correct !
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Solved.