Question 227894
Let {{{w}}}= ml of water to be added
In words:
(final ml of salt)/(final ml of salt + water) = 125%
Initially I have:
{{{.25*150 = 37.5}}} ml salt in solution
I can now write my equation:
{{{37.5/(150 + w) = .15}}}
Multiply both sides by {{{150 + w}}}
{{{37.5 = .15*(150 + w)}}}
{{{37.5 = 22.5 + .15w}}}
{{{.15w = 15}}}
{{{w = 100}}} ml
100 ml of water needs to be added
check:
{{{37.5/(150 + w) = .15}}}
{{{37.5/(150 + 100) = .15}}}
{{{37.5/250 = .15}}}
{{{37.5 = .15*250}}}
{{{37.5 = 37.5}}}
OK