Using a system of equation, we have that:
a)
- x, which is the cost of on-site service.
- y, which is the cost of at-store service.
- z, which is the cost of by-mail service.
b)
The system is:
c)
The cost of one on-site repair service is of $90.
Item a:
The variables are:
- x, which is the cost of on-site service.
- y, which is the cost of at-store service.
- z, which is the cost of by-mail service.
Item b:
On-site service costs <u>3 times as much as at-store service</u>, thus:
By mail service costs <u>$10 less than at-store</u> service, thus:
Last week, the shop completed <u>15 services on-site, 40 services at-store, and 5 services by mail for total sales of $3100</u>, thus:
The system is:
Item c:
- The cost of one on-site repair service is x.
- First, replacing the first two equations into the third, we find y, and then with it we find x.
Then
The cost of one on-site repair service is of $90.
A similar problem is given at brainly.com/question/24823220
Answer:
63.5
Step-by-step explanation:
Answer:
The third exterior angle is 
Step-by-step explanation:
Given
Required
The third exterior angle 
The exterior angles of a triangle add up to 360 degrees.
So:
Make 
the subject
Substitute known values
Using the z-distribution, the p-value would be given as follows:
b) 0.0086.
<h3>What are the hypothesis tested?</h3>
At the null hypothesis we test if the means are equal, hence:
At the alternative hypothesis, it is tested if they are different, hence:
<h3>What are the mean and the standard error for the distribution of differences?</h3>
For each sample, they are given as follows:
Hence, for the distribution of differences, they are given by:
.
<h3>What is the test statistic?</h3>
The test statistic is given by:
In which 
is the value tested at the null hypothesis.
Hence:
z = -2.63.
Using a z-distribution calculator, for a two-tailed test, with z = -2.63, the p-value is of 0.0086.
Hence option B is correct.
More can be learned about the z-distribution at brainly.com/question/13873630
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C is the answer to the problem
