Leah thinks of a number.
She then does the following operations:
Multiply by 3, subtract 4, multiply by 2 then add 16 (in that order).
She finds that the number she ends up with is 8 times her original number.
What was Leah's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Leah's original number be x.
First operation gives 3x
Second operation gives 3x- 4
Third operation gives 2(3x- 4)
Fourth operation gives 2(3x- 4) + 16
This is equal to 8 times the original number
2(3x - 4) + 16 = 8x
6x- 8 + 16 = 8x
x = 4
Leah's original number was 4.
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