It should be 7days if that’s what you meant by says
Answer:
We need to sample at least 37 weeks of data.
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{1-0.98}{2} = 0.01](https://tex.z-dn.net/?f=%5Calpha%20%3D%20%5Cfrac%7B1-0.98%7D%7B2%7D%20%3D%200.01)
Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so ![z = 2.327](https://tex.z-dn.net/?f=z%20%3D%202.327)
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%2A%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%7D)
We want 98% confidence that the sample mean is within $500 of the population mean, and the population standard deviation is known to be $1300
This is at least n weeks, in which n is found when ![M = 500, \sigma = 1300](https://tex.z-dn.net/?f=M%20%3D%20500%2C%20%5Csigma%20%3D%201300)
So
![M = z*\frac{\sigma}{\sqrt{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%2A%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%7D)
![500 = 2.327*\frac{1300}{\sqrt{n}}](https://tex.z-dn.net/?f=500%20%3D%202.327%2A%5Cfrac%7B1300%7D%7B%5Csqrt%7Bn%7D%7D)
![500\sqrt{n} = 2.327*1300](https://tex.z-dn.net/?f=500%5Csqrt%7Bn%7D%20%3D%202.327%2A1300)
![\sqrt{n} = \frac{2.327*1300}{500}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B2.327%2A1300%7D%7B500%7D)
![(\sqrt{n})^{2} = (\frac{2.327*1300}{500})^{2}](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E%7B2%7D%20%3D%20%28%5Cfrac%7B2.327%2A1300%7D%7B500%7D%29%5E%7B2%7D)
![n = 36.6](https://tex.z-dn.net/?f=n%20%3D%2036.6)
Rounding up
We need to sample at least 37 weeks of data.
4 x 3 = 12
1 x 3 = 3
12 + 3 = 15
answer
15 square units
Answer:
She will cycle 85.169 miles in the third week.
(round if needed)
Step-by-step explanation:
56÷100=0.56 (this is 1%)
0.56 x 15 + 56 = 64.4 (you find 15% then add 56 (the original amount) because it's an increase of 15%)
repeat for the other 3 weeks
64.4÷100=0.644
0.644 x 15 + 64.4 = 74.06
74.06÷100=0.7406
0.7406 x 15 + 74.06 = 85.169
2pt=1qt
1pt=1/2qt
therefor
multiply 2 and 3/4 by 1/2
(2 and 3/4) times 1/2=(2+3/4) times 1/2=2 times 1/2+3/4 times 1/2=2/2+3/8=1+3/8=1 and 3/8 pt