Answer:
The critical value is T = 1.895.
The 90% confidence interval for the mean repair cost for the washers is between $48.159 and $72.761
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 8 - 1 = 6
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 6 degrees of freedom(y-axis) and a confidence level of
. So we have T = 1.895, which is the critical value.
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 60.46 - 12.301 = $48.159
The upper end of the interval is the sample mean added to M. So it is 60.46 + 12.301 = $72.761
The 90% confidence interval for the mean repair cost for the washers is between $48.159 and $72.761
Answer:
Step-by-step explanation:
a) -x-4(1-x) =
−
2
x
−4
(
1
−
x
)
.
2
x
−
4
b) 3(5x-2)-5(3-4x) =
3
⋅
(5
x
−
2
)
−
5
⋅
(
5
−
4
x
)
35
x − 31
c) √2(3-x)-2(1-x√2) =
√
2
x
⋅
(
3
−x
)
−
2
⋅(
1
−
x
√
2
)
.
2
x
√
2
+
3
√
2
x
-√
2
x
x
−
2
Answer: 30.8%
Step-by-step explanation:
Given
Total students receiving financial aid are 6101
Students who are graduate and receiving financial aid are 1879
Probability is the ratio of the favorable and total outcomes
So, the probability is given by
The answer is (x+5) (3x+2)
Answer:

Step-by-step explanation:

take derivative with respect to t

derivative of e^t is e^t
derivative of 0.23t is 0.23

Apply chain rule

