Question 948381
 Company A Spent a total of ${{{11}}} million on advertising in fiscal year {{{2010}}},{{{ 2011}}}, and {{{2012}}}. 

your attempt to set-up the system was perfect, system just need to be solved

so, 
in year {{{2010}}} company spent {{{x}}} million, 
in year {{{2011}}} company spent {{{y}}} million, 
in year {{{2012}}} company spent {{{z}}} million, 

total: {{{x+y+z=11}}}........eq.1

The amount{{{z}}}  spent in {{{2012}}} was three times the amount {{{x}}} spent in {{{2010}}}. 
{{{z=3x}}}........eq.2

The amount{{{y}}} spent in {{{2011}}} was ${{{3}}} million less than the amount {{{z}}} spent in {{{2012}}}. 
{{{y=z-3}}} ........eq.3

solve the system:
{{{x+y+z=11}}}........eq.1
{{{z=3x}}}........eq.2
{{{y=z-3}}} ........eq.3
-----------------------------------------
start with {{{y=z-3}}} ........eq.3 substitute {{{z}} from eq.2
{{{y=3x-3}}}.......3a

go to
 {{{x+y+z=11}}}........eq.1 substitute {{{z}} from eq.2 and {{{y}}} from eq.3a
 {{{x+3x-3+3x=11}}}......  solve for {{{x}}}

{{{7x=11+3}}}
{{{7x=14}}}
{{{x=14/7}}}
{{{highlight(x=2)}}}

go to {{{y=3x-3}}}.......3a substitute {{{2}} for  {{{x}}

{{{y=3*2-3}}}
{{{y=6-3}}}
{{{highlight(y=3)}}}

go to {{{z=3x}}}........eq.2 substitute {{{2}} for  {{{x}}

{{{z=3*2}}}
{{{highlight(z=6)}}}

so, each year on advertising was spent: 

in year {{{2010}}} company spent {{{2}}} million, 
in year {{{2011}}} company spent {{{3}}} million, 
in year {{{2012 }}}company spent {{{6}}} million,