Question 1116889
Let {{{ x }}} = pounds of non-fat yogurt needed
{{{ 50 - x }}} = pounds of regular 4% yogurt needed
{{{ .04*( 50 - x ) }}} = pounds of fat in the 4% yogurt
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{{{ ( .04*( 50 - x ) ) / 50 = .01 }}}
{{{ .04*( 50 - x ) = .5 }}}
{{{ 2 - .04x = .5 }}}
{{{ .04x = 1.5 }}}
{{{ x = 37.5 }}}
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37.5 pounds of non-fat yogurt are needed
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check:
{{{ 50 - x = 50 - 37.5 }}}
{{{ 50 - x = 12.5 }}} pounds of 4% yogurt needed
{{{ .04*12.5 = .5 }}} pounds of fat in 4% yogurt
{{{ .5 / 50 = .01 }}}
{{{ 1 / 100 = .01 }}}
OK