91影视

Mean of 106 samples of body temperatures is 98.20掳F $\left(\stackrel{炉}{x}\right)$and the standard deviation is 0.62掳F (s).

The level of confidence is 95%.

The sample size of mean body temperatures is 106 which is greater than 30.Therefore, the distribution can be approximated as normal distribution.

Assume that the sample is randomly selected and the population standard deviation is unknown.

Thus, t-distribution would be used to find the confidence interval.

Confidence interval for mean is expressed as $\stackrel{炉}{x}-E<渭<\stackrel{炉}{x}+E$.

Here, $\stackrel{炉}{x}$is the sample mean and E is the margin of error.

$E=t_{\frac{伪}{2}}脳\frac{s}{\sqrt{n}}$

Where, $t_{\frac{伪}{2}}$is the critical value with level of significance for normal distribution.

Here, $\stackrel{炉}{x}$represents the sample mean of the Mean Body Temperature data and $渭$ represents the population mean of the Mean Body Temperature data.

The 95% confidence interval for mean body temperature is computed as,

$$\begin{gathered} \stackrel{炉}{x}-E<渭<\stackrel{炉}{x}+E \\ 98.20-0.1194<渭<98.20+0.1194 \\ 98.08<渭<98.32 \end{gathered}$$

Therefore, 95% confidence interval is $\left(98.08掳F,98.32掳F\right)$.

The 95% confidence interval of the mean body temperature for the entire population is $98.{08}^{0}F<渭<98.{32}^{0}F$.

The confidence interval does not contain in 95% confidence interval.

Hence, the result suggests that the common belief that 鈥渢he mean body temperature is 98.6掳F鈥� is not true.