Question 908462
All the ingredients of the recipe
get increased by the same factor
Let {{{ k }}} = the factor of the increase
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For the boiling water:
{{{ 2 = k*( 2/3) }}}
{{{ k = (3/2)*2 }}}
{{{ k = 3 }}}
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So, the sugar gets increased by 
the factor {{{ k = 3 }}}
{{{ k*2 = 3*2 }}}
{{{ k*2 = 6 }}}
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6 cups of sugar are needed