Question 1144848
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Let x be the total volume, now unknown.  Then


    {{{1/x}}} = 0.3


is the equation for the total volume.


From the equation,


    x = {{{1/0.3}}} = {{{10/3}}} gallons = {{{3}}}{{{1/3}}} gallons.


Hence, you should add  {{{3}}}{{{1/3}}} - 1 = {{{2}}}{{{1/3}}} gallons of water.   <U>ANSWER</U>
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