Select the correct answer from each drop-down menu.

Tonya and Leo each bought a cell phone at the same time. The trade-in values, in dollars, of the cell phones are modeled by the given functions, where [tex]$x$[/tex] is the number of months that each person has owned the phone.

\begin{tabular}{|c|c|c|c|}
\hline
Tonya's Phone & \multicolumn{3}{|c|}{Leo's Phone} \\
\hline
\multirow{4}{}{[tex]$f(x)=490(0.88)^x$[/tex]} & \multirow[t]{4}{}{[tex]$\bullet$[/tex]} & [tex]$x$[/tex] & [tex]$g(x)$[/tex] \\
\hline
& & 0 & 480 \\
\hline
& & 2 & 360 \\
\hline
& & 4 & 270 \\
\hline
\end{tabular}

[tex]$\square$[/tex] phone has the greater initial trade-in value.

During the first four months, the trade-in value of Tonya's phone decreases at an average rate [tex]$\square$[/tex] the trade-in value of Leo's phone.



Answer :

Let's analyze the problem step by step using the given functions and values to fill in the blanks correctly.

First, let's determine the initial trade-in value for each phone when [tex]\( x = 0 \)[/tex]:

- For Tonya's phone [tex]\( f(x) = 490(0.88)^x \)[/tex]:
[tex]\[ f(0) = 490(0.88)^0 = 490 \text{ dollars} \][/tex]
- For Leo's phone, from the table, [tex]\( g(0) = 480 \text{ dollars} \)[/tex].

Between Tonya and Leo, Tonya's phone has the greater initial trade-in value (\[tex]$490 vs. \$[/tex]480).

Now, let's calculate the average rate of decrease in trade-in value over the first four months for both phones.

### Tonya's Phone
The trade-in values at [tex]\( x = 0, 2, 4 \)[/tex] for Tonya's phone:
[tex]\[ f(0) = 490(0.88)^0 = 490 \text{ dollars} \][/tex]
[tex]\[ f(2) = 490(0.88)^2 = 490 \times 0.7744 = 379.456 \text{ dollars} \][/tex]
[tex]\[ f(4) = 490(0.88)^4 = 490 \times 0.59969536 = 293.8507264 \text{ dollars} \][/tex]

From [tex]\( x = 0 \)[/tex] to [tex]\( x = 4 \)[/tex] months, let's compute the average rate of decrease:

[tex]\[ \text{Average rate of decrease} = \frac{f(0) - f(4)}{4 - 0} = \frac{490 - 293.8507264}{4} \approx 49.0373184 \text{ dollars per month} \][/tex]

### Leo's Phone
The trade-in values from the table:
[tex]\[ g(0) = 480 \text{ dollars} \][/tex]
[tex]\[ g(2) = 360 \text{ dollars} \][/tex]
[tex]\[ g(4) = 270 \text{ dollars} \][/tex]

From [tex]\( x = 0 \)[/tex] to [tex]\( x = 4 \)[/tex] months, let's compute the average rate of decrease:

[tex]\[ \text{Average rate of decrease} = \frac{480 - 270}{4 - 0} = \frac{210}{4} = 52.5 \text{ dollars per month} \][/tex]

### Conclusion
- Initial Trade-in Value: Tonya's phone has the greater initial trade-in value.
- Rate of Decrease: The trade-in value of Tonya's phone decreases at an average rate slower than the trade-in value of Leo's phone (49.0373184 vs. 52.5 dollars per month).

So the filled-in statements would be:

[tex]\[ \boxed{\text{Tonya's}} \ \text{phone has the greater initial trade-in value.} \][/tex]

[tex]\[ \text{During the first four months, the trade-in value of Tonya's phone decreases at an average rate} \ \boxed{\text{slower than}} \ \text{the trade-in value of Leo's phone.} \][/tex]