Question 1014128
Let {{{ x }}} = ounces of the 1st spice needed
{{{ .3x }}} = ounces of salt in 1st spice
{{{ .65*175 }}} = ounces of salt in the 2nd spice
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{{{ ( .3x + .65*175 ) / ( x + 175 ) = .5 }}}
{{{ ( .3x + 113.75 ) / ( x + 175 ) = .5 }}}
{{{ .3x + 113.75 = .5*( x + 175 ) }}}
{{{ .3x + 113.75 = .5x + 87.5 }}}
{{{ .2x = 26.25 }}}
{{{ x = 131.25 }}}
131.25 ounces of the 1st spice are needed
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check answer:
{{{ ( .3x + .65*175 ) / ( x + 175 ) = .5 }}}
{{{ ( .3*131.25 + .65*175 ) / ( 131.25 + 175 ) = .5 }}}
{{{ ( 39.375 + 113.75 ) / 306.25 = .5 }}}
{{{ 153.125 / 306.25 = .5 }}}
{{{ 153.125 = .5*306.25 }}}
{{{ 153.125 = 153.125 }}}
OK