Kayla thinks of a number.
She then does the following operations:
Multiply by 3, subtract 6, multiply by 3 then add 42 (in that order).
She finds that the number she ends up with is 12 times her original number.
What was Kayla's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Kayla'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) + 42
This is equal to 12 times the original number
3(3x  6) + 42 = 12x
9x 18 + 42 = 12x
...
x = 8
Kayla's original number was 8.
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