Examine would this work?
Choose a number. Double it. Add nine. Add your original number. Divide by three. Add four. Subtract your original number. Your result is seven.
Let our original number be n. Then we are doing the following operations.
n→2n→2n+9→2n+9=3n+9→3n+93=n+3→n+3+4=n+7→n+7−n=7
Therefore whatever we take the Value of n the Result Would be 7