In $2010,$ the city of Houston, Texas, collected

$$24,112,054$ in fi nes from motorists because of

traffi c violations caught by red$-$light cameras. The

cost of operating the system was $$8,432,372.$ The

net profi t$,$ that is$,$ profi t after operating costs, is

split equally $($that is$,50\%$ each$)$ between the city

and the operator of the camera system. What will

be the rate of return over a $3-$year period to the

contractor that paid for, installed, and operates the

system, if its initial cost was $$9,000,000$ and the

profi t for each of the $3$ years is the same as it was

in $2010?$