Jeremiah thinks of a number.
He then does the following operations:
Multiply by 3, subtract 6, multiply by 3 then add 39 (in that order).
He finds that the number he ends up with is 12 times his original number.
What was Jeremiah's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Jeremiah's original number be x.
First operation gives 3x
Second operation gives 3x- 6
Third operation gives 3(3x- 6)
Fourth operation gives 3(3x- 6) + 39
This is equal to 12 times the original number
3(3x - 6) + 39 = 12x
9x- 18 + 39 = 12x
x = 7
Jeremiah's original number was 7.
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