Question 700831
The key is the amount of iodine does not change, 
only the alcohol.
{{{ .035*100 = 3.5 }}} ounces of iodine in 3.5% solution
Let {{{ a }}} = ounces of alcohol to be added
{{{ 3.5 / ( 100 + a ) = .015 }}}
{{{ 3.5 = .015*( 100 + a ) }}}
{{{ 3.5 = 1.5 + .015a }}}
{{{ .015a = 2 }}}
{{{ a = 133.333 }}}
133.333 ounces of alcohol must be added
check:
{{{ 3.5 / ( 100 + a ) = .015 }}}
{{{ 3.5 / ( 100 + 133.333 ) = .015 }}}
{{{ 3.5 = .015*233.333 }}}
{{{ 3.5 = 3.5 }}}
OK