Answer:
He must survey 123 adults.
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 .
The margin of error is:
Assume that a recent survey suggests that about 87% of adults have heard of the brand.
This means that
90% confidence level
So , z is the value of Z that has a p-value of , so .
How many adults must he survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage?
This is n for which M = 0.05. So
Rounding up:
He must survey 123 adults.
Answer:
x = 136/11
, y = 68/11
Step-by-step explanation:
Solve the following system:
{6 x - y = 68
2 y = x
Hint: | Choose an equation and a variable to solve for.
In the second equation, look to solve for x:
{6 x - y = 68
2 y = x
Hint: | Reverse the equality in 2 y = x in order to isolate x to the left hand side.
2 y = x is equivalent to x = 2 y:
{6 x - y = 68
x = 2 y
Hint: | Perform a substitution.
Substitute x = 2 y into the first equation:
{11 y = 68
x = 2 y
Hint: | Choose an equation and a variable to solve for.
In the first equation, look to solve for y:
{11 y = 68
x = 2 y
Hint: | Solve for y.
Divide both sides by 11:
{y = 68/11
x = 2 y
Hint: | Perform a back substitution.
Substitute y = 68/11 into the second equation:
{y = 68/11
x = 136/11
Hint: | Sort results.
Collect results in alphabetical order:
Answer: {x = 136/11
, y = 68/11
Answer:
Step-by-step explanation:
Given
Required
Determine the percentage change
Percentage change is calculated as;
<em>Hence, the percentage change is approximately 8.8%</em>
By definition, the arc length is given by:
arc = R * theta * ((2 * pi) / 360)
Where,
theta: angle in degrees
R: radio
We have then:
(Arc) QPT if <QZT = 120:
theta = 360-120 = 240 degrees
R = 13.5 units
Substituting values we have:
(Arc) QPT = R * theta * ((2 * pi) / 360)
(Arc) QPT = (13.5) * (240) * ((2 * pi) / 360)
(Arc) QPT = 56.55 units
Answer:
(Arc) QPT = 56.55 units
Answer:
x = 35
Step-by-step explanation:
Since m1=m2 :