1. **State the problem:** Manny can put together 3 airplane models in 4.5 hours and 4 models in 6 hours. We need to find the time it takes to put together 1 model, write an equation for time $y$ based on number of models $x$, and find the time for 8 models.
2. **Fill in the table:** Given values:
Number of models (x) | Total time in hours (y)
1 | ?
2 | ?
3 | 4.5
4 | 6
3. **Calculate the unit rate (time per model):**
We find the rate using the two points (3, 4.5) and (4, 6).
Calculate the rate of change (slope):
$$\text{slope} = \frac{6 - 4.5}{4 - 3} = \frac{1.5}{1} = 1.5$$
This means it takes 1.5 hours per model.
4. **Find time for 1 model:**
Using the point (3, 4.5), check if consistent:
$$4.5 = 3 \times 1.5$$
This matches, so unit rate is 1.5 hours per model.
5. **Write the equation:**
Time $y$ is proportional to number of models $x$:
$$y = 1.5x$$
6. **Fill in missing table values:**
For $x=1$: $$y = 1.5 \times 1 = 1.5$$
For $x=2$: $$y = 1.5 \times 2 = 3$$
7. **Calculate time for 8 models:**
$$y = 1.5 \times 8 = 12$$
**Final answer:** It will take Manny 12 hours to put together 8 airplane models.
Model Assembly Time 49Cfad
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.