Answer:
A sample of 18 is required.
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:
Now, we have to find z in the Z-table as such z has a p-value of
.
That is z with a pvalue of
, so Z = 1.88.
Now, find the margin of error M as such
In which
is the standard deviation of the population and n is the size of the sample.
A previous study indicated that the standard deviation was 2.2 days.
This means that 
How large a sample must be selected if the company wants to be 92% confident that the true mean differs from the sample mean by no more than 1 day?
This is n for which M = 1. So



Rounding up:
A sample of 18 is required.
Answer:
1. 96%
2. $6000
3. 176
4. 20%
Step-by-step explanation:
1. 1/5 of 80% is 16%. 80+16=96
2. 25% of 8000 is 2000. 8000-2000= 6000.
3. 10% increase of 200 is 20. 20+200=220. 20 percent of 220 is 44. 220-44=176
4. if you increase the original salary by 20%, then decreasing it by 20% of the new salary will give you the old salary.
Answer:
Step-by-step explanation:
7+3-2=3+7-2
Quadrant General Form of Point in this Quadrant Example
I (+, +) (5, 4)
II (−, +) (−5, 4)
III (−, −) (−5, −4)
IV (+, −) (5, −4)
Answer: 4,5
Step-by-step explanation: