Question

In: Statistics and Probability

A survey of 700 high school students in our stat showed that 216 felt unsafe in...

A survey of 700 high school students in our stat showed that 216 felt unsafe in their local school. Construct a 95% confidence interval for the proportion of students who felt unsafe.

Expert Solution

Solution :

Given that,

Point estimate = sample proportion = = x / n = 216 / 700 = 0.309

1 - = 1 - 0.309 = 0.691

Z/2 = 1.96

Margin of error = E = Z / 2 * $\sqrt$ (( * (1 - )) / n)

= 1.96 * ( $\sqrt$ ((0.309 * 0.691) / 700)

Margin of error = E = 0.034

A 95% confidence interval for population proportion p is ,

- E < p < + E

0.309 - 0.034 < p < 0.309 + 0.034

0.275 < p < 0.343

The 95% confidence interval for the population proportion p is : 0.275 , 0.343

orchestra answered 3 years ago

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