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Compute a 99% confidence interval for the mean weight of toxic substance per gram of mold culture. State the assumption you make about the population.

User Cgrim
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Complete Question

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Answer:

The 99% confidence interval is
2.4309 < &nbsp;\mu < &nbsp; 4.9328

Explanation:

From the question we are told that

The data is 3, 2,5, 3, 2, 6, 5,4.5, 3, 3, and 4

The sample size is n = 11

Generally the sample mean is mathematically represented as


\= x &nbsp;= &nbsp;(\sum x_i)/(n)

=>
\= x &nbsp;= &nbsp;(3+ 2+5+ \cdots +4 )/(11)

=>
\= x &nbsp;= &nbsp;3.6818

Generally the sample standard deviation is mathematically represented as


\sigma &nbsp;= &nbsp;\sqrt{(\sum [ x_i - \= x ] )/(n) }

=>
\sigma &nbsp;= &nbsp;\sqrt{([ 3 - 3.6818 ]^2 +[ 2 - 3.6818 ]^2 + \cdots + [ 4 - 3.6818 ]^2 &nbsp; )/(11) }

=>
\sigma &nbsp;= &nbsp;1.3091

Given that the confidence interval is 99% then the level of significance is mathematically represented as


\alpha= (100 - 99) \%

=>
\alpha= 0.01

Given that the sample size is small we will making use of t distribution table

Generally from the t distribution table the critical value of at a degree of freedom of is


t_{(\alpha )/(2) , 10 } =3.16927267

Generally the margin of error is mathematically represented as


E = &nbsp;3.16927267 &nbsp;* &nbsp;(1.3091 )/(√(11) )


E = 1.251

Generally 99% confidence interval is mathematically represented as


3.6818 -1.251 < &nbsp;p < 3.6818 + 1.251

=>
2.4309 < &nbsp;\mu < &nbsp; 4.9328

Compute a 99% confidence interval for the mean weight of toxic substance per gram-example-1
User Horgen
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