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In: Statistics and Probability

2.   A survey of 200 students is selected randomly on a large university campus. They are...

2.   A survey of 200 students is selected randomly on a large university campus. They are asked if they use a laptop in class to take notes. The result of the survey is that 128 of the 200 students responded ”yes."

A.   Find 98% confidence interval

B.   How would the confidence interval change if the confidence level had been 90% instead of 98%?

C.   How would the confidence interval change if the sample size had been 300 instead of 200? (Assume the same sample proportion.)

D.   How large would the sample size have to be to make the margin of error one fourth as big in the 98% confidence interval?

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