Answer:
The 95% confidence interval for the fraction of all shoppers during the year whose visit was because of a coupon they'd received in the mail is (0.2016, 0.2694).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the z-score that has a p-value of 
.
A store randomly samples 603 shoppers over the course of a year and finds that 142 of them made their visit because of a coupon they'd received in the mail.
This means that 
95% confidence level
So 
, z is the value of Z that has a p-value of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
The 95% confidence interval for the fraction of all shoppers during the year whose visit was because of a coupon they'd received in the mail is (0.2016, 0.2694).
Answer:
If they are both red, 7/22
If both blue, 1/22
Yellow, 1/66
Step-by-step explanation:
7/12 times 6/11 (both decrease by one because there is no replacement)
3/12 times 2/11
2/12 times 1/11
Answer:
y = x + 3
Step-by-step explanation:
Slope-intercept form is represented by the formula 
. We can write an equation in point-slope form first, then convert it to that form.
1) First, find the slope of the line. Use the slope formula 
and substitute the x and y values of the given points into it. Then, simplify to find the slope, or 
:
Thus, the slope of the line must be 1.
2) Now, since we know a point the line intersects and its slope, use the point-slope formula 
and substitute values for , 
, and 
. From there, we can convert the equation into slope-intercept form.
Since represents the slope, substitute 1 in its place. Since and represent the x and y values of a point the line intersects, choose any one of the given points (either one is fine) and substitute its x and y values into the equation, too. (I chose (0,3).) Finally, isolate y to find the answer:
Answer:
y = 5/8x + 12
Step-by-step explanation:
Slope = change in y/change in x
slope = 5/8
Using y = mx + b find b.
y = 5/8x + b
-2 = 5/8(-4) + b
b = 1/2
y = 5/8x + 12
<em>good luck, i hope this helps :)</em>
