Chapter 3 - Section 3.2 - Problem Solving and Business Applications Using Systems of Equations - Exercise Set - Page 205: 21

$x=96,y=204$

As per the statement: $x+y=300$ and $0.75x+0.50y=(0.58)(300)$ After plugging the variable $x$ form the first equation in the second equation, we get $0.75(300-x)+0.50y=(0.58)(300) \implies -0.25y=-51$ or, $y=204$ Now, $x+204=300 \implies x=96$ Thus, $x=96,y=204$