Question 991554
Let {{{ x }}} = grams of raisins needed
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{{{ ( 20x + 12*18 ) / ( x + 12 ) = 19.25 }}}
{{{ 20x + 216 = 19.25*( x + 12 ) }}}
{{{ 20x + 216 = 19.25x + 231 }}}
{{{ .75x = 15 }}}
{{{ x = 15/.75 }}}
{{{ x = 20 }}}
20 grams of raisins are needed
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check:
{{{ ( 20*20 + 12*18 ) / ( 20 + 12 ) = 19.25 }}}
{{{ ( 400 + 216 ) / 32 = 19.25 }}}
{{{ 616/32 = 19.25 }}}
{{{ 616 = 616 }}}
OK