A publishing company produced a record high of 180 books today. In the 9 days prior to today, the same publishing company had produced an average (arithmetic mean) of \(x\) books per day. If today's record high increased average daily production to \(y\) books per day, what is \(x\) in terms of \(y\)?
\(A)\quad \dfrac{9y+180}{10}\)
\(B) \quad \dfrac{10y+180}{9}\)
\(C) \quad \dfrac{9y−180}{9}\)
\(D) \quad \dfrac{10y−180}{9}\)
\(E) \quad \dfrac{10y}{9}−10\)
[spoiler]OA=D[/spoiler]
Source: Manhattan GMAT
\(A)\quad \dfrac{9y+180}{10}\)
\(B) \quad \dfrac{10y+180}{9}\)
\(C) \quad \dfrac{9y−180}{9}\)
\(D) \quad \dfrac{10y−180}{9}\)
\(E) \quad \dfrac{10y}{9}−10\)
[spoiler]OA=D[/spoiler]
Source: Manhattan GMAT
