Zachary thinks of a number.
He then does the following operations:
Multiply by 3, subtract 3, multiply by 2 then add 36 (in that order).
He finds that the number he ends up with is 12 times his original number.
What was Zachary's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Zachary's original number be x.
First operation gives 3x
Second operation gives 3x 3
Third operation gives 2(3x 3)
Fourth operation gives 2(3x 3) + 36
This is equal to 12 times the original number
2(3x  3) + 36 = 12x
6x 6 + 36 = 12x
...
x = 5
Zachary's original number was 5.
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