Question 976071
Let {{{ w }}} = liters of water to be removed
{{{ .54*65 = 35.1 }}} liters of acid in 54% solution
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{{{ 35.1 / ( 65 - w ) = .78 }}}
{{{ 35.1 = .78*( 65 - w ) }}}
{{{ 35.1 = 50.7 - .78w }}}
{{{ .78w = 50.7 - 35.1 }}}
{{{ .78w = 15.6 }}}
{{{ w = 20 }}}
20 liters of water must be taken out
( note that no acid is taken out )