The heights of 1000 students at a local school were recorded and found to be approximated by the normal curve below. Which answe
r could represent the mean and standard deviation for these data ?
1 answer:
Answer:
The mean of the distribution of heights of students at a local school is 63 inches and the standard deviation is 4 inches.
Step-by-step explanation:
The normal curve approximating the distribution of the heights of 1000 students at a local school is shown below.
For a normal curve, the mean, median and mode are the same and represents the center of the distribution.
The center of the normal curve below is at the height 63 inches.
Thus, the mean of the distribution of heights of students at a local school is 63 inches.
The standard deviation represents the spread or dispersion of the data.
From the normal curve it can be seen that values are equally distributed, i.e. the difference between two values is of 4 inches.
So, the standard deviation is 4 inches.
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The appropriate choice is ...
C. The slope of the first equation is not graphed the right way.
A correct graph is shown below.
C. The slope of the first equation is not graphed the right way.
A correct graph is shown below.
Answer:
The 99.7% confidence interval for the mean price of all new mobile homes is ($60,672, $65,622).
Step-by-step explanation:
<em>The question is incomplete:</em>
<em>The prices in thousands of dollar are:</em>
<em>66.6, 69.8, 58.4, 57.3, 63.1, 61.8, 56, 72.7, 61.8, </em>
<em>66.9, 72.6, 63.1, 58.7, 65.9, 61.1, 56.1, 49.9, 72.6, </em>
<em>49, 56.4, 72.6, 60.1, 65, 64.8, 56.5, 52, 53.2, </em>
<em>56.4, 75.4, 76.3, 60.5, 74.6, 57, 69.2, 62.7, 77.2.</em>
<em />
We have a sample of n=36 new mobile homes.
The mean of this sample is:
The population standard deviation is σ=7.5 (in thousands of dollars).
The critical value of z for a 99.7% CI is z=2.97.
Then, we can calculate the margin of error as:
Now we can calculate the lower and upper bound of the confidence interval as:
The 99.7% confidence interval for the mean price of all new mobile homes is ($60,672, $65,622).
