1. You really blew this test. You scored 0.9 standard deviations below the mean. To make...

1. You really blew this test. You scored 0.9 standard deviations below the mean. To make you feel better you calculate the proportion of students who did even worse than you. What is that proportion?

2. If you have a sample size of 20 cases, what is the minimum t-score needed to be statistically significant at the 0.01 level?

3. What is the sampling error for N=1,250? (assume proportion (p) =.5)

Expert Solution

(there are more than 1 questions, as per policy i am answering first question)

1.

z = -0.9

P(z<-0.90) = 0.1841 {from table}

therfore the proportion of students that did worse than you is 0.1841

(please upvote)

P(z<Z) table :

orchestra answered 2 years ago

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