Mariah thinks of a number.
She then does the following operations:
Multiply by 2, subtract 2, multiply by 2 then add 52 (in that order).
She finds that the number she ends up with is 10 times her original number.
What was Mariah's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Mariah's original number be x.
First operation gives 2x
Second operation gives 2x- 2
Third operation gives 2(2x- 2)
Fourth operation gives 2(2x- 2) + 52
This is equal to 10 times the original number
2(2x - 2) + 52 = 10x
4x- 4 + 52 = 10x
x = 8
Mariah's original number was 8.
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