Question 1033211
Let {{{ x }}} = ml of 95% solution needed
{{{ .95x }}} = ml of alcohol in 95% solution
{{{ .15*225 = 33.75 }}} = ml of alcohol in 15% solution
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{{{ ( .95x + 33.75 ) / ( x + 225 ) = .8 }}}
{{{ .95x + 33.75 = .8*( x + 225 ) }}}
{{{ .95x + 33.75 = .8x + 180 }}}
{{{ .15x = 146.25 }}}
{{{ x = 975 }}}
975 ml of the 95% solution is needed
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check:
{{{ ( .95*975 + 33.75 ) / ( 975 + 225 ) = .8 }}}
{{{ ( 926.25 + 33.75 ) / 1200 = .8 }}}
{{{ 960 / 1200 = .8 }}}
{{{ 960 = 960 }}}
OK