Answer:
12,156,2029
Step-by-step explanation:
<h3>Given</h3>
- room height is x feet
- room length is 3x feet
- room width is 3x feet
- a door 3 ft wide by 7 ft tall
<h3>Find</h3>
- The net area of the wall, excluding the door
<h3>Solution</h3>
The area of the wall, including the door, is the room perimeter multiplied by the height of the room. The room perimeter is the sum of the lengths of the four walls.
... gross wall area = (3x +3x +3x +3x)·x = 12x²
The area of the door is the product of its height and width.
... door area = (7 t)×(3 ft) = 21 ft²
Then the net wall area, exclusive of the door is ...
... net wall area = gross wall area - door area
... net wall area = 12x² -21 . . . . square feet
Answer: point estimate = 3.88
Margin of error = 0.63
Step-by-step explanation:
Confidence interval is written in the form,
(Point estimate - margin of error, Point estimate + margin of error)
The sample mean, x is the point estimate for the population mean. Let m represent the margin of error. Since the confidence interval is given as (3.25 , 4.51), it means that
x - m = 3.25
x + m = 4.51
Adding both equations, it becomes
2x = 7.76
x = 7.76/2
x = 3.88
Substituting x = 3.88 into x + m = 4.51, it becomes
3.88 + m = 4.51
m = 4.51 - 3.88
m = 0.63
Answer:
(A) 0.006593 or 0.6593%
(B) 0.01538 or 1.538%
Step-by-step explanation:
The total number of possibilities to pick 3 parts out of 15 possible parts is given by the following combination:
![n=\frac{15!}{(15-3)!3!}=\frac{15*14*13}{3*2*1}\\n=455\ ways\\](https://tex.z-dn.net/?f=n%3D%5Cfrac%7B15%21%7D%7B%2815-3%29%213%21%7D%3D%5Cfrac%7B15%2A14%2A13%7D%7B3%2A2%2A1%7D%5C%5Cn%3D455%5C%20ways%5C%5C)
(A) There are only three possibilities for which the inspector finds exactly one nonconforming part (NCC, CNC, CCN). Therefore, the probability is:
![P(N=1) = \frac{3}{455}=0.006593 =0.6593\%](https://tex.z-dn.net/?f=P%28N%3D1%29%20%3D%20%5Cfrac%7B3%7D%7B455%7D%3D0.006593%20%3D0.6593%5C%25)
(B) There are three possibilities for which the inspector finds exactly one nonconforming part, three possibilities for two nonconforming parts (NNC, CNN, NCN), and one possibility for all nonconforming parts (NNN). The probability that the inspector finds at least one nonconforming part is:
![P(N>0) =P(N=1)+P(N=2)+P(N=3) \\P(N>0) = \frac{3}{455}+ \frac{3}{455}+ \frac{1}{455}\\P(N>0) =0.01538 =1.538\%](https://tex.z-dn.net/?f=P%28N%3E0%29%20%3DP%28N%3D1%29%2BP%28N%3D2%29%2BP%28N%3D3%29%20%5C%5CP%28N%3E0%29%20%3D%20%5Cfrac%7B3%7D%7B455%7D%2B%20%5Cfrac%7B3%7D%7B455%7D%2B%20%5Cfrac%7B1%7D%7B455%7D%5C%5CP%28N%3E0%29%20%3D0.01538%20%3D1.538%5C%25)