a clothing store is raising the prices of all its sweaters by $ 3.00. write an expression that could be used to find the new pri
1 answer:
You might be interested in
Answer:
We conclude that the population mean is 24.
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 24
Sample mean, = 22.8
Sample size, n = 100
Alpha, α = 0.05
Sample standard deviation, s = 8.3
First, we design the null and the alternate hypothesis
We use Two-tailed z test to perform this hypothesis.
Formula:
Putting all the values, we have
We calculate the p-value with the help of standard z table.
P-value = 0.1498
Since the p-value is greater than the significance level, we accept the null hypothesis. The population mean is 24.
Now,
Since, the z-statistic lies in the acceptance region which is from -1.96 to +1.96, we accept the null hypothesis and conclude that the population mean is 24.
Answer:
D
Step-by-step explanation:
We have the piecewise function:
And we want to find x such that f(x)=1.
So, let's substitute 1 for f(x):
This has two equations. So, we can separate them into two separate cases. Namely:
Let's solve for x in each case.
Case I:
We have:
Add 1 to both sides:
Let's cancel out the fraction by multiplying both sides by -2. So:
The right side cancels:
Flip:
So, x is -4.
Case II:
We have:
Flip:
This is the solution for our second case.
So, we have:
Now, can check to see if we have to to remove solution(s) that don't work.
Note that x=-4 is the solution to our first equation.
The first equation is defined only if x is less than -2.
-4 <em>is </em>less than -2. So, x=-4 is indeed a solution.
x=1 is the solution to our second equation.
The second equation is defined only if x is greater than or equal to -2.
1 <em>is</em> greater than or equal to -2. So, x=1 is <em>also </em>a solution.
Therefore, our two solutions are:
Out of our answer choices, we can pick D.
And we're done!