Question

In: Statistics and Probability

It was found that in a sample of 90 teenage boys, 70% of themhave received...

  1. It was found that in a sample of 90 teenage boys, 70% of them have received speeding tickets. What is the 90% confidence interval of the true proportion of teenage boys who have received speeding tickets

  2. Given the above information, how many boys must be sampled to be within 2% of true proportion in a 90% confidence interval?

  3. If no information is given for the proportion, how many boys must be sampled?

Solutions

Expert Solution

Confidence interval :

First Sample size:

Second Sample size

orchestra answered 2 years ago
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