Question 653649
Let {{{ x }}} = oz of 50% antifreeze solution needed
{{{ .5x }}} = oz of antifreeze in 50% antifreeze solution
{{{ .8*10 = 8 }}} oz of antifreeze in 80% antifreeze solution
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{{{ ( .5x + 8 ) / ( x + 10 ) = .6 }}}
{{{ .5x + 8 = .6*( x + 10 ) }}}
{{{ .5x + 8 = .6x + 6 }}}
{{{ .1x = 2 }}}
{{{ x = 20 }}}
20 oz of 50% antifreeze solution is needed
check answer:
{{{ ( .5*20 + 8 ) / ( 20 + 10 ) = .6 }}}
{{{ ( 10 + 8 ) / 30 = .6 }}}
{{{ 18/30 = .6 }}}
{{{ 18 = .6*30 }}}
{{{ 18 = 18 }}}
OK