Answer:
Look below
Step-by-step explanation:
The mean of the sampling distribution always equals the mean of the population.
μxˉ=μ
The standard deviation of the sampling distribution is σ/√n, where n is the sample size
σxˉ=σ/n
When a variable in a population is normally distributed, the sampling distribution of for all possible samples of size n is also normally distributed.
If the population is N ( µ, σ) then the sample means distribution is N ( µ, σ/ √ n).
Central Limit Theorem: When randomly sampling from any population with mean µ and standard deviation σ, when n is large enough, the sampling distribution of is approximately normal: ~ N ( µ, σ/ √ n ).
How large a sample size?
It depends on the population distribution. More observations are required if the population distribution is far from normal.
A sample size of 25 is generally enough to obtain a normal sampling distribution from a strong skewness or even mild outliers.
A sample size of 40 will typically be good enough to overcome extreme skewness and outliers.
In many cases, n = 25 isn’t a huge sample. Thus, even for strange population distributions we can assume a normal sampling distribution of the mean and work with it to solve problems.
Answer:
I think the last one try I guess if not then ask someone else
Answer:
Step-by-step explanation:
Area of a rectangle = width × length
Therefore, to find the length of the rectangle, we need to divide the area by the width.
Using long division:
Therefore, the <u>length</u> of the rectangle is:
You didn't include the table but I found this table for the same statement, so I will answer you based on the next table:
Runner distance time
Arabella 7,299 feet 561 seconds
Bettina 3,425 yards 13 minutes, 12 seconds
Chandra 8,214 feet 0,195 hours
Divya 1,62 miles 732 seconds
To answer the question you must find the rate for each runner and then calculate the time to run 3.1 miles at each rate.
First you need to convert the data to obtain the rate in miles per second.
These are the main conversion identities:
1 mile = 5280 feet
1 mile = 1760 yards
1 hour = 3600 seconds
1 hour = 60 minutes
1 minute = 60 seconds
Arabella:
rate: 7,229 feet / 561 seconds * (1 mile / 5280 feet) =
= 0.00244 mile/second
Time to run 3.1 miles: V = d / t => t = d / V = 3.1 miles / 0.00244 mile/second = 1270 seconds
Bettina:
13 minutes + 12 seconds = 13*60 seconds +12 seconds = 792 seconds
rate = 3425 yards / 792 seconds * 1 mile / 1760 yards = 0.00246 mile/seconds
Time to run 3.1 miles = 3.1 miles / 0.00246 mile/second = 1260 seconds
Chandra:
rate = 8214 feet / 0.195 hours * 1 mile / 5280 feet * 1hour / 3600 seconds =
= 0.00222 seconds
Time = 3.1 mile / 0.00222 seconds = 0.389 hour = 1396 seconds
Divya:
rate = 1.62 miles / 732 seconds = 0.00221 seconds
Time = 3.1 mile / 0.00221 seconds = 1403 seconds
Now you can find the difference between fhe last and the first 1403 seconds - 1260 seconds = 143 seconds
That is equivalent to 2.38 seconds.
