Answer: A
Step-by-step explanation:
Confidence interval for the difference in the two proportions is written as
Difference in sample proportions ± margin of error
Sample proportion, p = x/n
Where x = number of success
n = number of samples
For the first treatment,
x = 35
n1 = 50
p1 = 35/50 = 0.7
For the second treatment,
x = 16
n2 = 40
p2 = 16/40 = 0.4
Margin of error = z√[p1(1 - p1)/n1 + p2(1 - p2)/n2]
To determine the z score, we subtract the confidence level from 100% to get α
α = 1 - 0.99 = 0.01
α/2 = 0.01/2 = 0.005
This is the area in each tail. Since we want the area in the middle, it becomes
1 - 0.005 = 0.995
The z score corresponding to the area on the z table is 2.576. Thus, the z score for 99% confidence level is 2.576
Margin of error = 2.576 × √[0.7(1 - 0.7)/50 + 0.4(1 - 0.4)/40]
= 2.576 × 0.10099504938
= 0.26
Confidence interval = 0.7 - 0.4 ± 0.26
= 0.3 ± 0.26
Option A is correct
Answer:14
Step-by-step explanation:
16/18, which is 8/9 reduced
The answer is between B and C.
There are two different versions of standard deviation. The population standard deviation will use the formula shown in choice C, while the sample standard deviation uses the formula in choice B.
The instructions arent fully clear which your teacher wants. I would ask them for further clarification. I'm sorry I'm not more helpful.
Answer:
909 times
Step-by-step explanation:
$500,000/550= 909