Answer:
a. The null and alternative hypothesis can be written as:

b. A Type I error is made when a true null hypothesis is rejected. In this case, it would happen if it is concluded that the actual mean outstanding credit card debt of college undergraduate is significantly less than $3173, when in fact it does not.
A Type II error is made when a false null hypothesis is failed to be rejected. In this case, the actual mean outstanding credit card debt of college undergraduate is in fact less than $3173, but the test concludes there is no enough evidence to claim that.
Step-by-step explanation:
We have a prior study of the mean outstanding credit card debt of college undergraduate that states that it was $3173 in 2010.
A researcher believes that this amount has decreased since then.
Then, he has to perform a hypothesis test where the null hypothesis states that the mean is still $3173 and an alternative hypothesis that states that the actual credit card debt is significantly smaller than $3173.
The null and alternative hypothesis can be written as:

I hope this is what you were looking for.
Answer:
Step-by-step explanation:
(3x-2)+(2x+16)=90
5x=76
x=15.2
I hope this helps
Answer:
The range of the function is:
Range R = {14, 17, 20}
Step-by-step explanation:
Given the function

We also know that range is the set of values of the dependent variable for which a function is defined.
In other words,
- Range refers to all the possible sets of output values on the y-axis.
We are given that the domain of the function is:
Domain D = {4, 5, 6}
Now,
substituting x = 4 in the function
f(4) = 3(4) + 2
f(4) = 12 + 2
f(4) = 14
substituting x = 5 in the function
f(5) = 3(5) + 2
f(5) = 15 + 2
f(5) = 17
substituting x = 6 in the function
f(6) = 3(6) + 2
f(6) = 18 + 2
f(6) = 20
Thus, we conclude that:
at x = 4, y = 14
at x = 5, y = 17
at x = 6, y = 20
Thus, the range of the function is:
Range R = {14, 17, 20}
Answer:
90 stamps from Canada, 108 stamps from the United States, and 135 stamps from the Rest of the World
Step-by-step explanation:
Since this is a problem of proportion we can use the Rule of three to solve this. We do this by multiplying the diagonal available values and dividing by the third value in order to get the missing variable, which in this case would be the number of stamps in the other country. Like so...
1.5 <=====> 135 stamps
1.2 <=====> x stamps (United States)
(1.2 * 135) / 1.5 = 108 stamps (United States)
1.5 <=====> 135 stamps
1 <=====> x stamps (Canada)
(1 * 135) / 1.5 = 90 stamps (Canada)
Finally, we can see that Katie had 90 stamps from Canada, 108 stamps from the United States, and 135 stamps from the Rest of the World. All creating a ratio or 1:1.2:1.5