$\"\"$

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The random sample size is $\"\"$ .

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$\"\"$ of adult americians had obtained bacheors degree, thus $\"\"$ .

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The value of $\"\"$ .

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The value of mean is $\"\"$ .

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Substitute $\"\"$ and $\"\"$ .

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$\"\"$

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The value is $\"\"$ .

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The standard deviation is $\"\"$ .

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Substitute $\"\"$ , $\"\"$ and $\"\"$ .

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$\"\"$ .

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The standard deviation is $\"\"$ .

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$\"\"$

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Find the probability $\"\"$ .

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$\"\"$ .

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Find the corresponding $\"\"$ -values for $\"\"$ and $\"\"$ .

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The value of $\"\"$ is $\"\"$ .

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For $\"\"$ , $\"\"$ and $\"\"$

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$\"\"$

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$\"\"$ .

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For $\"\"$ , $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$ .

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The approximate area corresponds to $\"\"$ is $\"\"$ .

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Therefore, the probability that in a random sample of $\"\"$ people , between $\"\"$ is $\"\"$ .

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$\"\"$

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The probability that in a random sample of $\"\"$ people , between $\"\"$ is $\"\"$ .