Answer:
90% confidence interval: (70.41,86.89)
Step-by-step explanation:
We are given the following in the question:
Point estimate = 78.65
Margin of error, E = 8.24
Confidence level = 90%
Significance level = 10%
Formula:

Putting the values, we get,


(70.41,86.89) is the required 90% confidence interval.
The answer would be: <span>99.0%
</span>
The disease is rare with a prevalence of <span>one out of every thousand people have it. That means, the chance of Roberto has the disease without any test would be 1/1000 or 0.1%
The test sensitivity is 99%, which mean 99% of people with positive test result would have the disease. The chance is should not be influenced by the disease prevalence. </span>
Formula :

Plug in the values :

----------------------------------
Answer:550----------------------------------
15 plates = $5.99 (wow that's expensive)
They need 100
100/15= Somewhere around 7
5.99*7=41.93
Answer: They will need 7 packs which costs in total
$41.93