1. **Problem Statement:**
We are given two equations based on the cost of coffee and toast:
- 7 cups of coffee + 4 pieces of toast = 655
- 5 cups of coffee + 3 pieces of toast = 475
We need to find the cost of one cup of coffee and one piece of toast.
2. **Define variables:**
Let $x$ be the cost of one cup of coffee.
Let $y$ be the cost of one piece of toast.
3. **Write the system of equations:**
$$\begin{cases} 7x + 4y = 655 \\ 5x + 3y = 475 \end{cases}$$
4. **Solve the system using elimination:**
Multiply the first equation by 3 and the second by 4 to align coefficients of $y$:
$$\begin{cases} 21x + 12y = 1965 \\ 20x + 12y = 1900 \end{cases}$$
5. **Subtract the second equation from the first:**
$$ (21x + 12y) - (20x + 12y) = 1965 - 1900 $$
$$ \cancel{21x} + \cancel{12y} - \cancel{20x} - \cancel{12y} = 65 $$
$$ x = 65 $$
6. **Substitute $x=65$ into the second original equation:**
$$ 5(65) + 3y = 475 $$
$$ 325 + 3y = 475 $$
7. **Solve for $y$:**
$$ 3y = 475 - 325 $$
$$ 3y = 150 $$
$$ y = \frac{150}{3} $$
$$ y = 50 $$
**Final answer:**
Cost of one cup of coffee $x = 65$
Cost of one piece of toast $y = 50$
Coffee Toast Cost 3A407F
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