You have a 20% increase with a 25% decrease? what do i do
1 answer:
You might be interested in
Answer:
Step-by-step explanation:
Factor top and bottom.
The numerator is a difference of two squares, and the denominator is a quadratic.
=
=
If x does not equal -1 and does not equal 4, we can cancel the common factors in italics to give
=
=
Answer:
The null and alternative hypotheses are:
Under the null hypothesis, the test statistic is:
Where:
is the sample mean
is the sample standard deviation
is the sample size
Now, the right tailed t critical value at 0.05 significance level for df = n-1 = 10-1 = 9 is:
Since the t statistic is less than the t critical value at 0.05 significance level, therefore,we fail to reject the null hypothesis and conclude that there is not sufficient evidence to support the claim that the average phone bill has increased.