<PRE><B>Question 1043223</B>
First you need to convert cubic yards
to gallons. I looked it up ( google ) and got:
1 cubic yard  = 201.974 US liquid gallons
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Now find how many cubic yards are in the tank:
width = {{{ 2 }}} yds
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Note that 200% just means a factor of {{{ 2 }}}
{{{ 2 }}} yds = twice the depth
depth = {{{ (1/2)*2 = 1 }}} yd
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Note that 100% GREATER THAN means 100% 
in addition to, so
Length = twice the width
Length = {{{ 2*2 = 4 }}} yds
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Volume of tank = width x length x depth
Volume = {{{ 2*1*4 = 8 }}} cubic yards
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Just in terms of dimensions:
[ cubic yards ] x [ gallons / [ 1 cubic yard ] = [ gallons ]
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{{{ 8*( 201.974 / 1 ) = 1615.792 }}} gallons
1,615.792 gallons is the volume of the tank
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