Question 491167
Let {{{ x }}} = pounds of peanuts to be added
{{{ .2*10 = 2 }}} pounds of peanuts in 10 pound bag
In words:
(final pounds of peanuts) / (final pounds of mixture) = 80%
{{{ ( 2 + x ) / ( 10 + x ) = .8 }}}
{{{ 2 + x = .8*( 10 + x ) }}}
{{{ 2 + x = 8 + .8x }}}
{{{ .2x = 8 - 2 }}}
{{{ .2x = 6 }}}
{{{ x = 30 }}}
30 pounds of peanuts should be added
check:
{{{ ( 2 + x ) / ( 10 + x ) = .8 }}}
{{{ ( 2 + 30 ) / ( 10 + 30 ) = .8 }}}
{{{ 32 / 40 = .8 }}}
{{{ 32 = 32 }}}
OK