Question

After years of rapid growth, illegal immigration into the United States has declined, perhaps owing to the recession and increased border enforcement by the United States (Los Angeles Times, September 1, 2010). While its share has declined, California still accounts for 35% of the nation’s estimated 11.3 million undocumented immigrants.

a. In a sample of 60 illegal immigrants, what is the probability that more than 21% live in California? (Round “z” value to 2 decimal places, and final answer to 4 decimal places.)

b. In a sample of 120 illegal immigrants, what is the probability that more than 21% live in California? (Round “z” value to 2 decimal places, and final answer to 4 decimal places.)

c. Comment on the reason for the difference between the computed probabilities in parts a and b.

• As the sample number increases, the probability of more than 21% also increases, due to the lower z value and decreased standard error.

• As the sample number increases, the probability of more than 21% also increases, due to the lower z value and increased standard error.

Answer 1

Refer Standard normal table/Z-table to find the probability.

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Refer Standard normal table/Z-table to find the probability.

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As the sample number increases, the probability of more than 21% also increases, due to the lower z value and decreased standard error.