Audrey thinks of a number.
She then does the following operations:
Multiply by 3, subtract 7, multiply by 2 then add 26 (in that order).
She finds that the number she ends up with is 9 times her original number.
What was Audrey's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Audrey's original number be x.
First operation gives 3x
Second operation gives 3x 7
Third operation gives 2(3x 7)
Fourth operation gives 2(3x 7) + 26
This is equal to 9 times the original number
2(3x  7) + 26 = 9x
6x 14 + 26 = 9x
...
x = 4
Audrey's original number was 4.
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