91影视

To describe the shape, center, and spread of the distribution of shark lengths. And to enter the data into the calculator and make a histogram. Then calculate one-variable statistics.

Let, the sharks have lengths of 44 feet.
Below are some descriptive statistics:

And the histogram as:

Shark lengths are nearly symmetric, peaking at $16$, and range from $9.40$feet to $22.8$ feet at the maximum.
As a result, Shape: approximately bell-shaped and symmetric.
Center: Mean is $15.5884$and median is $15.75$
Spread: standard deviation is $2.5499$.

To calculate the percent of observations that fall within one, two, and three standard deviations of the mean.

According to the output:
Mean is $\stackrel{炉}{x}=15.586$
Sample standard deviation is $s=2.550$
$\stackrel{炉}{x}-s=13.036$
$\stackrel{炉}{x}+s=18.136$
The percent of interval as:

$(68.26\%)68.2\%$

$\stackrel{炉}{x}-2s=10.487$
$\stackrel{炉}{x}+2s=20.686$
Then the percent of interval as:
$(95.44\%)95.5\%$
$\stackrel{炉}{x}-3s=7.937$
$\stackrel{炉}{x}+3s=23.236$

Then the percent of interval as:
$\text{(99.73\%)}100.0\%$
Approximately $68.2$percent of the data values fall inside one standard deviation, according to the $68-95-99.7$criterion.
Within two standard deviations of the mean, $95.5$percent of the data values fall, and within three standard deviations of the mean, $100$ percent of the data values fall.
As a result,
One standard deviation is $68.2\%$
Two standard deviations is $95.5\%$
Three standard deviations is $100\%$.

To use the calculator to construct a Normal probability plot. And to interpret the plot.

A Normal probability plot from Minitab is shown below:

Except for one small shark and one enormous shark length, the plot is reasonably linear, indicating that the Normal distribution is reasonable.
As a result, a Normal probability plot is made.
The pattern in the Normal probability plot is roughly linear and roughly normal.

To write a brief summary of the assessment that combines the findings from (a) through (c).

The results of parts (a), (b), and (c) show that shark lengths are roughly normal.
Because the normal probability plot was roughly normal and the histogram was approximately bell-shaped, it was roughly normal.
As a result, the observations are approximately Normal.