Emma thinks of a number.
She then does the following operations:
Multiply by 3, subtract 7, multiply by 2 then add 28 (in that order).
She finds that the number she ends up with is 8 times her original number.
What was Emma's original number?
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This question is best answered by forming an algebraic equation then solving it. Let Emma'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) + 28
This is equal to 8 times the original number
2(3x - 7) + 28 = 8x
6x- 14 + 28 = 8x
x = 7
Emma's original number was 7.
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