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In: Statistics and Probability

A researcher reported that 71.8% of all email sent in a recent month was spam. A...

A researcher reported that 71.8% of all email sent in a recent month was spam. A system manager at a large corporation believes that the percentage at his company may be 71%. He examines a random sample of 500 emails received at an email server, and finds that 377 of the messages are spam. Can you conclude that the percentage of emails that are spam is greater than 71% ? Use both α=0.10 and α=0.01 levels of significance and the P-value method with the TI-84 Plus calculator.

a. state null and alternative hypothesis. what tail is the hypothesis test?

b. Compute the value of the test statistic.

c. Using α=0.10, can you conclude that greater than 71% of emails are spam?

d. Using α=0.01, can you conclude that greater than 71% of emails are spam?

e. state conclusion

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Expert Solution

orchestra answered 1 year ago
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