Question 270276
In words:
(ounces of iodine in final solution)/(ounces of final solution) = 25%
Let {{{x}}} = ounces of pure iodine I need to add
given:
{{{.15*24 = 3.6}}} ounces of iodine in 15% solution
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{{{(3.6 + x)/(24 + x) = .25}}}
{{{3.6 + x = .25*(24 + x)}}}
{{{3.6 + x = 6 + .25x}}}
{{{.75x = 6 - 3.6}}}
{{{.75x = 2.4}}}
{{{x = 2.4/.75}}}
{{{x = 3.2}}}
3.2 ounces of pure iodine must be added
check:
{{{(3.6 + x)/(24 + x) = .25}}}
{{{(3.6 + 3.2)/(24 + 3.2) = .25}}}
{{{6.8/27.2 = .25}}}
{{{6.8 = .25*27.2}}}
{{{6.8 = 6.8}}}
OK