sat suite question viewer
The expression represents the result of decreasing a positive quantity by what percent?
Explanation
Choice D is correct. Let represent the percent by which the positive quantity is decreased to result in . The value of can be found by solving the equation . Since is a common factor of each of the terms on the left-hand side of this equation, the equation can be rewritten as . Dividing each side of this equation by yields . Multiplying each side of this equation by yields . Subtracting from each side of this equation yields . Dividing each side of this equation by yields . Therefore, the expression represents the result of decreasing the positive quantity by .
Choice A is incorrect. Decreasing the quantity by yields , or , not .
Choice B is incorrect. Decreasing the quantity by yields , or , not .
Choice C is incorrect. Decreasing the quantity by yields , or , not .