## anonymous one year ago Two studies were completed in California. One study in northern California involved 1,000 patients; 74% of them experienced flulike symptoms during the month of December. The other study, in southern California, involved 500 patients; 34% of them experienced flulike symptoms during the same month. Which study has the smallest margin of error for a 98% confidence interval?

1. anonymous

The northern California study with a margin of error of 3.2%. The southern California study with a margin of error of 3.2%. The northern California study with a margin of error of 4.9%. The southern California study with a margin of error of 4.9%.

2. kropot72

The margin of error is found from $\large 2.33\sqrt{\frac{p(1-p)}{n}}$ where p is the sample proportion expressed as a decimal. Therefore the margin of error for the northern California study is $\large 2.33\sqrt{\frac{0.74\times0.26}{1000}}=you\ can\ calculate.$ Now you need to use the same procedure to find the margin of error for the southern California study.

3. anonymous

4. anonymous

@kropot72

5. anonymous

because both A and D are the answer but only one can be chosen!

6. anonymous

ok, A is the correct choice!

7. anonymous

for future users!