Question 883928
Let {{{ x }}} = the length of the 
3rd piece of wire in inches
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The 1st piece is {{{ 2x }}} inches long
The 2nd piece is also {{{ 2x }}} inches long
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Now I can say:
{{{ x + 2x + 2x = 200 }}}
{{{ 5x = 200 }}}
{{{ x = 40 }}}
and
{{{ 2x = 80 }}}
The 3rd piece is 40 inches long
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check answer:
{{{ x + 2x + 2x = 200 }}}
{{{ 40 + 80 + 80 = 200 }}}
{{{ 200 = 200 }}}
OK