Question 184883
Let {{{w}}} = pounds of walnuts needed
Let {{{m}}} = pounds of the final mixture
In words:
(pounds of walnuts)x(price per pound) + (pounds of chips)x(price per pound)
=(pounds of mixture)x(price per pound)
given:
Price of walnuts in mixture = {{{2.4w}}}
Price of chips in mixture = {{{3*3 = 9}}}
Price of mixture = {{{2.58m}}}
{{{m = 3 + w}}}
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{{{2.4w + 9 = 2.58m}}}
{{{2.4w + 9 = 2.58*(3 + w)}}}
{{{2.4w + 9 = 7.74 + 2.58w}}}
{{{.18w = 1.26}}}
{{{w = 7}}}
7 pounds of walnuts are needed
check:
{{{2.4w + 9 = 2.58m}}}
{{{2.4*7 + 9 = 2.58m}}}
{{{16.8 + 9 = 2.58m}}}
{{{2.58m = 25.8}}}
{{{m = 10}}}
and
{{{m = 3 + w}}}
{{{10 = 3 + 7}}}
{{{10 = 10}}}
OK