Answer:
5-√9/4 4-3√-16 3+2√-9➗7
Step-by-step explanation:
That’s what i got
step by step explanation
Answer:
30+4?
Step-by-step explanation:
Answer:
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
![\alpha = \frac{1 - 0.8}{2} = 0.1](https://tex.z-dn.net/?f=%5Calpha%20%3D%20%5Cfrac%7B1%20-%200.8%7D%7B2%7D%20%3D%200.1)
Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 1.28.
Now, find the margin of error M as such
![M = z\frac{\sigma}{\sqrt{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%7D)
In which
is the standard deviation of the population and n is the size of the sample.
![M = 1.28\frac{1.5}{\sqrt{305}} = 0.1](https://tex.z-dn.net/?f=M%20%3D%201.28%5Cfrac%7B1.5%7D%7B%5Csqrt%7B305%7D%7D%20%3D%200.1)
The lower end of the interval is the sample mean subtracted by M. So it is 7.6 - 0.1 = 7.5
The upper end of the interval is the sample mean added to M. So it is 7.6 + 0.1 = 7.7
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
It is SAS because
1) it is given that sides are equal (AB=CD)
2)it is also given that angles B and C are equal
3) BC is a common side so it is equal in both triangles.
answer: SAS