$\"\"$

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The function is $\"\"$ .

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Where the total number of population is $\"\"$ .

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$\"\"$ is the number of days that have elapsed since the rumor began.

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Tthe number of people in a college community who have heard a certain rumor is $\"\"$ .

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Find how many days will elapse before 450 students have heard the rumor.

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Substitute $\"\"$ and $\"\"$ in $\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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From the definition $\"x$ if and only if $\"y$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ days will elapse before 450 students have heard the rumor.

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$\"\"$

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$\"\"$ days will elapse before 450 students have heard the rumor.