1. **State the problem:** Chris sold 180 cookies and cupcakes. Cupcakes cost $0.50 each, cookies cost $0.25 each, and total sales were $66. Find how many of each were sold. 2. **Identify variables:** Let $x$ = number of cupcakes sold. Let $y$ = number of cookies sold. 3. **List given information:** Total items sold: $x + y = 180$ Total money collected: $0.50x + 0.25y = 66$ 4. **Write the system of equations:** $$\begin{cases} x + y = 180 \\ 0.5x + 0.25y = 66 \end{cases}$$ 5. **Solve the system:** From the first equation, express $y$: $$y = 180 - x$$ Substitute into the second equation: $$0.5x + 0.25(180 - x) = 66$$ Simplify: $$0.5x + 45 - 0.25x = 66$$ $$0.25x + 45 = 66$$ $$0.25x = 21$$ $$x = \frac{21}{0.25} = 84$$ 6. **Find $y$:** $$y = 180 - 84 = 96$$ 7. **Interpretation:** Chris sold 84 cupcakes and 96 cookies. **Final answer:** $$\boxed{\text{Cupcakes} = 84, \quad \text{Cookies} = 96}$$