Question

the number of pounds of dog food that a pet store has is represented by the equation \\(y = -15x + 430\\), where \\(x\\) represents the number of days that the store is open and \\(y\\) represents the pounds of dog food in stock in the store. how many pounds of dog food will the pet store have after 21 days?

92
115
315
336

Explanation:

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<reasoning>

Identify the given equation and variable values

\[

$$\begin{aligned} &y = -15x + 430 \\ &x = 21 \end{aligned}$$

\]

Substitute the value of x into the equation

\[

$$\begin{aligned} &y = -15(21) + 430 \end{aligned}$$

\]

Calculate the final value of y

\[

$$\begin{aligned} &y = -315 + 430 \\ &y = 115 \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>92</mcq-option>
<mcq-correct>115</mcq-correct>
<mcq-option>315</mcq-option>
<mcq-option>336</mcq-option>
</answer>

<post_analysis>
{
"subject": "Mathematics",
"question_type": "Multiple Choice",
"knowledge_point": [
"Mathematics",
"Algebra",
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]
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Answer:

<pre_analysis>
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<reasoning>

Identify the given equation and variable values

\[

$$\begin{aligned} &y = -15x + 430 \\ &x = 21 \end{aligned}$$

\]

Substitute the value of x into the equation

\[

$$\begin{aligned} &y = -15(21) + 430 \end{aligned}$$

\]

Calculate the final value of y

\[

$$\begin{aligned} &y = -315 + 430 \\ &y = 115 \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>92</mcq-option>
<mcq-correct>115</mcq-correct>
<mcq-option>315</mcq-option>
<mcq-option>336</mcq-option>
</answer>

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