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WE:Business Development (Energy and Utilities)
Re: If y ≠ 0, what percent of y percent of 50 is 40 percent of y
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14 Jul 2018, 05:17
Explanation
The question already contains a variable (y). Use another variable to represent the desired value. Represent “what” with the variable x, and isolate x to solve. Notice that by the end, the y variables cancel out:
\(\frac{x}{100} \times \frac{y}{100} \times 50=\frac{40}{100}y\).
At this point, there are many options for simplifying, but do simplify before multiplying anything. Here is one way to simplify:
\(\frac{x}{100} \times \frac{y}{2} \times 50=\frac{2}{5}y\).
\(x=80.\)