Hannah thinks of a number.
She then does the following operations:
Multiply by 2, subtract 4, multiply by 2 then add 38 (in that order).
She finds that the number she ends up with is 10 times her original number.
What was Hannah's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Hannah's original number be x.
First operation gives 2x
Second operation gives 2x- 4
Third operation gives 2(2x- 4)
Fourth operation gives 2(2x- 4) + 38
This is equal to 10 times the original number
2(2x - 4) + 38 = 10x
4x- 8 + 38 = 10x
x = 5
Hannah's original number was 5.
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