Question 711427
Let {{{ w }}} = liters of water to be added
{{{ .2*10 = 2 }}} liters of salt in 20% solution
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{{{ 2 / ( w + 10 ) = .05 }}}
{{{ 2 = .05*( w + 10 ) }}}
{{{ 2 = .05w + .5 }}}
{{{ .05w = 1.5 }}}
{{{ w = 30 }}}
30  liters of water need to be added