Question 977491
Let {{{ a }}} = the number of residents
that town A used to have
{{{ 5000 - a }}} = the number of residents
that town B used to have
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{{{ .06a }}} = number of hispanics that
town A used to have
{{{ .12*( 5000 - a ) }}} = number of hispanics 
that town B used to have
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After merging, the town has:
{{{ .1056*5000 = 528 }}} hispanics
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Now I can say:
{{{ .06a + .12*( 5000 - a ) = 528 }}}
{{{ .06a + 600 - .12a = 528 }}}
{{{ .06a = 600 - 528 }}}
{{{ .06a = 72 }}}
{{{ a = 1200 }}}
and
{{{ 5000 - a = 5000 - 1200 }}}
{{{ 5000 - a = 3800 }}}
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Town A used to have 1200 residents
Town B used to have 3800 residents