Question 1047943
Let {{{ x }}} = quarts of water to be added
{{{ 12 - x }}} = quarts of the 30% vinegar solution
{{{ .3*( 12 - x ) }}} = quarts of vinegar in the 30% vinegar solution
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{{{ ( .3*( 12 - x ) ) / 12 = .25 }}}
{{{ ( 3.6 - .3x ) / 12 = .25 }}}
{{{ 3.6 - .3x = 3 }}}
{{{ .3x = 3.6 - 3 }}}
{{{ .3x = .6 }}}
{{{ x = 2 }}}
2 quarts of water are needed
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check the answer:
{{{ ( .3*( 12 - x ) ) / 12 = .25 }}}
{{{ ( .3*( 12 - 2 ) ) / 12 = .25 }}}
{{{ ( .3*10 ) / 12 = .25 }}}
{{{ 3 = .25*12 }}}
{{{ 3 = 3 }}}
OK