Question 877046
Find 12 pounds is what fraction of the mixture by weight.


{{{1/3+3/5+f=1}}}
{{{f=1-1/3-3/5}}}
{{{f=(15-5-9)/15}}}
{{{f=1/15}}}
12 pounds is {{{1/15}}} of the mixture.  That is, of the entire mixture.  The mixture is therefore 15 times 12 pounds.


m for pounds of entire mixture,
{{{12=(1/15)m}}}
{{{m=12*15}}}
{{{highlight(m=180)}}}