Question 834067
{{{ .15*10 = 1.5 }}} ml of alcohol in 15% solution
Let {{{ w }}} = ml of water to be added
{{{ 1.5 / ( 10 + w ) = .05 }}}
{{{ 1.5 = .05*( 10 + w ) }}}
{{{ 1.5 = .5 + .05w }}}
{{{ .05w = 1 }}}
{{{ w = 20 }}}
20 ml of water must be added