Question

the data in the table compares \\(x\\), the number of pages in a chapter, to \\(y\\), the amount of time, in minutes, spent reading. the function \\(y = 0.86x - 0.09\\) models the data in the table.

which is the best prediction for the number of pages in a chapter that takes 18 minutes to read?

15
17
19
21

Explanation:

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<reasoning>

Identify the given model and target value

The linear model is:
\[y = 0.86x - 0.09\]
where:

• \(x\) is the number of pages in a chapter.
• \(y\) is the time spent reading in minutes.

We are given \(y = 18\) minutes and need to find the best prediction for \(x\).

Solve the equation for x

Substitute \(y = 18\) into the equation:
\[18 = 0.86x - 0.09\]
\[18.09 = 0.86x\]
\[x = \frac{18.09}{0.86}\]
\[x \approx 21.03\]

Select the closest option

The calculated value \(x \approx 21.03\) is closest to \(21\).
</reasoning>

<answer>
<mcq-option>15</mcq-option>
<mcq-option>17</mcq-option>
<mcq-option>19</mcq-option>
<mcq-correct>21</mcq-correct>
</answer>

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"question_type": "Multiple Choice",
"knowledge_point": [
"Mathematics",
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Answer:

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<reasoning>

Identify the given model and target value

The linear model is:
\[y = 0.86x - 0.09\]
where:

• \(x\) is the number of pages in a chapter.
• \(y\) is the time spent reading in minutes.

We are given \(y = 18\) minutes and need to find the best prediction for \(x\).

Solve the equation for x

Substitute \(y = 18\) into the equation:
\[18 = 0.86x - 0.09\]
\[18.09 = 0.86x\]
\[x = \frac{18.09}{0.86}\]
\[x \approx 21.03\]

Select the closest option

The calculated value \(x \approx 21.03\) is closest to \(21\).
</reasoning>

<answer>
<mcq-option>15</mcq-option>
<mcq-option>17</mcq-option>
<mcq-option>19</mcq-option>
<mcq-correct>21</mcq-correct>
</answer>

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