Problem
You make oatmeal cookies and oatmeal bars for a bake sale. One batch of oatmeal cookies requires $c$ cups of oats, and one batch of oatmeal bars requires $b$ cups of oats. You make $X$ batches of oatmeal cookies and $Y$ batches of oatmeal bars. Which expression represents the total amount of oats (in cups) you need? A. $X c+Y b$ B. $c+b$ C. $X+Y$ D. $\frac{X}{c}+\frac{Y}{b}$
Solution
Step 1 ：Find the total amount of oats needed for making X batches of oatmeal cookies and Y batches of oatmeal bars: \(Xc + Yb\)
Step 2 ：The final answer is: \(\boxed{Xc + Yb}\)
