1. **State the problem:** Daniel bought three distinct types of toys with a total cost of 25. One toy costs 20 more than three times the sum of the other two toys. The total cost of the three toys multiplied by 5 equals 125.
2. **Define variables:** Let the costs of the three toys be $x$, $y$, and $z$.
3. **Write the system of linear equations:**
- Total cost: $$x + y + z = 25$$
- One toy costs 20 more than three times the sum of the other two: $$z = 3(x + y) + 20$$
- Total cost multiplied by 5 equals 125: $$5(x + y + z) = 125$$
4. **Simplify the third equation:**
$$5(x + y + z) = 125 \implies x + y + z = \frac{125}{5} = 25$$
This is the same as the first equation, so it does not add new information.
5. **Substitute $z$ from the second equation into the first:**
$$x + y + 3(x + y) + 20 = 25$$
$$x + y + 3x + 3y + 20 = 25$$
$$4x + 4y + 20 = 25$$
6. **Simplify:**
$$4x + 4y = 25 - 20 = 5$$
Divide both sides by 4:
$$\cancel{4}x + \cancel{4}y = \frac{5}{\cancel{4}} \implies x + y = \frac{5}{4}$$
7. **Find $z$ using $z = 3(x + y) + 20$:**
$$z = 3 \times \frac{5}{4} + 20 = \frac{15}{4} + 20 = \frac{15}{4} + \frac{80}{4} = \frac{95}{4}$$
8. **Summary:**
- $x + y = \frac{5}{4}$
- $z = \frac{95}{4}$
9. **Interpretation:** The system has infinitely many solutions for $x$ and $y$ satisfying $x + y = \frac{5}{4}$, and $z$ is fixed at $\frac{95}{4}$. The system is consistent and dependent.
10. **Example solution:** If $x = 1$, then $y = \frac{5}{4} - 1 = \frac{1}{4}$. So the costs could be $x=1$, $y=\frac{1}{4}$, $z=\frac{95}{4}$.
**Final answer:**
- System of equations:
$$\begin{cases} x + y + z = 25 \\ z = 3(x + y) + 20 \\ 5(x + y + z) = 125 \end{cases}$$
- Nature: Consistent and dependent with infinitely many solutions.
- Costs: $x$ and $y$ satisfy $x + y = \frac{5}{4}$, $z = \frac{95}{4}$.
Toy Costs 49870D
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