Answer:
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so 
Now, find M as such
In which 
is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 0.181 - 0.0140 = 0.167 cc/m³.
The upper end of the interval is the sample mean added to M. So it is 0.181 + 0.0140 = 0.195 cc/m³.
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.
Answer: The figure is a regular hexagon.
Step-by-step explanation:
Answer:
5.1
Step-by-step explanation:
Answer: 21
Step-by-step explanation:
Answer:
1399 sq. feet
Step-by-step explanation:
Now, the data given is
height of front of apartment = 60 feet
Width of front of apartment = 25 feet
So total are of front of apartment is = Height x Width
= 60 x 25
= 1500 sq. yards
Now for door
Height = 7 feet
Width = 3 feet
So, total are of door
= Height x Width
= 7 x 3
= 21 sq. yards
Now for each window
Height = 4 feet
Width = 2 feet
So, total are of one window
= Height x Width
= 4 x 2
= 8 sq. yards
Now note that, for 10 windows area will be
= 8 x 10
= 80 sq. yards
Now understand that we have to find the area for bricks, but bricks will cover entire front except the door and windows. So, we have to subtract area of door and windows from total front area of apartment.
Area for bricks = Total front area - (area of door + area of 10 windows)
Area for bricks = 1500 - 21 - 80
Area for bricks = 1399 sq. yards
