<PRE><B>Question 717756</B>
Let {{{ x }}} = pounds of cashews to be used
{{{ 6x }}} = cost of cashews used
{{{ 3*12 = 36 }}} = cost of peanuts used
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{{{ ( 6x + 36 ) / ( x + 12 ) = 4.2 }}}
{{{ 6x + 36 = 4.2*( x + 12 ) }}}
{{{ 6x + 36 = 4.2x + 50.4 }}}
{{{ 1.8x = 14.4 }}}
{{{ x = 8 }}}
8 pounds of cashews should be used
check answer:
{{{ ( 6*8 + 36 ) / ( 8 + 12 ) = 4.2 }}}
{{{ ( 48 + 36 ) / 20 = 4.2 }}}
{{{ 84/20 = 4.2 }}}
{{{ 84 = 84 }}}
OK
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