Answer:
0.3 years
Step-by-step explanation:
With problems like these, I always like to start by breaking down the information into smaller pieces.
μ = 13.6
σ = 3.0
Survey of 100 self-employed people
(random variable) X = # of years of education
So now we have some notation, where μ represents population mean and σ represents population standard deviation. Hopefully, you already know that the sample mean of x-bar is the same as the population mean, so x-bar = 13.6. Now, the question asks us what the standard deviation is. Since the sample here is random, we can use the Central Limit Theorem, which allows us to guess that a distribution will be approximately normal for large sample sizes (that is, n ≥ 30). In this case, our sample size is 100, so that is satisfied. We're also told our sample is random, so we're good there, too. Now all we have to do is plug some stuff in.
The Central Limit Theorem says that for large values of n, x-bar follows an approximately normal distribution with sample mean = μ and sample standard deviation = σ/√n. So, with that info, all we need to do to find the standard deviation of x-bar is to plug our σ and n into the above formula.
σ(x-bar) = σ/√n
σ(x-bar) = 3.0/√100
σ(x-bar) = 0.3
So your answer here is .3 years.
Answer:
880 high-quality version
Step-by-step explanation:
I think the below is your full question:
<em>A Web music store offers two versions of a popular song. The size of the standard version is 2.1megabytes (MB). The size of the high-quality version is 4.5 MB. Yesterday, there were 1290 downloads of the song, for a total download size of 4821 MB. How many downloads of the high-quality version were there?</em>
Here is my answer:
Let x is the number of high-quality version
So the number of standard version= 1290 - x
We also know: total download size of 4821 MB. which means:
4.5x + 2.1(1290-x) = 4821
<=> 4.5x+2709-2.1x=4821
<=> 2.4x=2112
<=> x=880
So there were 880 high-quality version
Answer:
5
Step-by-step explanation:
To find the slope, you use rise/run. In this case... the rise is 5 up and the run is 1 across. Therefore it is 5/1 which is the same as 5. Hope this helped!
Answer:
The store sold 2,210 footballs.
Step-by-step explanation:
Answer:
u add 45 + 45 +90 that’s 180 and all triangles equal 180
Step-by-step explanation: