Answer: aA 90% confidence interval for the population proportion of adults in the U.S. who have donated blood in the past two years = (0.163,0.189)
Step-by-step explanation:
Let p = population proportion of adults in the U.S. who have donated blood in the past two years.
Given: A Gallup survey of 2322 adults (at least 18 years old) in the U.S. found that 408 of them have donated blood in the past two years.
Sample size: n= 2322
Sample proportion ![q=\dfrac{408}{2322}=0.176](https://tex.z-dn.net/?f=q%3D%5Cdfrac%7B408%7D%7B2322%7D%3D0.176)
Critical z-value for 90% confidence level : z*=1.645
The confidence interval for population proportion:
![q\pm z^*(\sqrt{\dfrac{q(1-q)}{n}})](https://tex.z-dn.net/?f=q%5Cpm%20z%5E%2A%28%5Csqrt%7B%5Cdfrac%7Bq%281-q%29%7D%7Bn%7D%7D%29)
A 90% confidence interval for the population proportion of adults in the U.S. who have donated blood in the past two years:
![0.176\pm (1.645)(\sqrt{\dfrac{0.176(1-0.176)}{2322}})\\\\=0.176\pm (1.645)(0.0079)\\\\=(0.176\pm0.013)\\\\=(0.176-0.013,0.176+0.013))\\\\=(0.163,0.189)](https://tex.z-dn.net/?f=0.176%5Cpm%20%281.645%29%28%5Csqrt%7B%5Cdfrac%7B0.176%281-0.176%29%7D%7B2322%7D%7D%29%5C%5C%5C%5C%3D0.176%5Cpm%20%281.645%29%280.0079%29%5C%5C%5C%5C%3D%280.176%5Cpm0.013%29%5C%5C%5C%5C%3D%280.176-0.013%2C0.176%2B0.013%29%29%5C%5C%5C%5C%3D%280.163%2C0.189%29)
Hence,
Let m = the total number of medals.
To find the total number of medals we can use either of the clues they gave us.
If Tara's team received 8 medals and that was 1/3 of the medals. That must mean that:
m x 1/3 = 8
What number divided by 3 is 8? Well, that is 24. Thus, the total number of medals is 24.
Note: we can check to see if 1/2 of 24 is 12, the total number of medals Jennifer team received, and it checks out!
Answer:
c = 83
b = 79
a = 101
d = 97
.
.........................
Answer:
4a2
Step-by-step explanation:
For a cube the lateral surface area would be the area of the four sides. If the edge of the cube has length a, the area of one square face Aface = a ⋅ a = a2. Thus the lateral surface of a cube will be the area of four faces: 4a2.