Juan thinks of a number.
He then does the following operations:
Multiply by 3, subtract 6, multiply by 2 then add 48 (in that order).
He finds that the number he ends up with is 12 times his original number.
What was Juan's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Juan's original number be x.
First operation gives 3x
Second operation gives 3x- 6
Third operation gives 2(3x- 6)
Fourth operation gives 2(3x- 6) + 48
This is equal to 12 times the original number
2(3x - 6) + 48 = 12x
6x- 12 + 48 = 12x
x = 6
Juan's original number was 6.
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