Question 739687
Let {{{ w }}} = ml of pure water to be added
{{{ .35*195 = 68.25 }}} ml of alcohol in 35% mixture
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{{{ 68.25 / ( 195 + w ) = .15 }}}
{{{ 68.25 = .15*( 195 + w ) }}}
{{{ 68.25 = 29.25 + .15w }}}
{{{ .15w = 39 }}}
{{{ w = 260 }}}
260 ml of pure water to be should be added
check:
{{{ 68.25 / ( 195 + w ) = .15 }}}
{{{ 68.25 / ( 195 + 260 ) = .15 }}}
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