In: Statistics and Probability
Use the two-proportions z-interval procedure to obtain
the required confidence interval for the difference between two
population proportions. Assume that independent simple random
samples have been selected from the two populations.
A survey of students at one college found that 57 of 96 randomly
selected freshmen and 85 of 118 randomly selected sophomores lived
off campus. Find a 98% confidence interval for the difference
between the proportions of freshmen and sophomores at this college
who live off campus.
-0.278 to 0.025 |
||
0.468 to 0.721 |
||
-0.254 to 0.721 |
||
0.444 to 0.744 |
Therefore, based on the data provided, the 98% confidence interval for the difference between the population proportions p1−p2 is −0.278<p<0.025
OPTION A is correct
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