What number did Janet pick if she added 7 to the number, multiplied the sum by 2, subtracted 4, and the final result was 28?
CEMC Pascal
Solution
We undo Janet's steps to find the initial number.
To do this, we start with 28, add 4 (to get 32), then divide the sum by 2 (to get 16), then subtract 7 (to get 9).
Thus, Janet's initial number was 9.
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