Answer:
CosB = 0.8
Step-by-step explanation:
We know
CosB = b/h
And given, b = 12 and h =15
The confidence interval for the mean usage of water is (18.7,20.5).
Given population standard deviation of 2.4, mean of 19.5 gallons per day and confidence interval of 98%.
We have to find the confidence interval for the mean usage of water.
To find out the confidence interval we have to first find margin of error.
μ=19.5
σ=2.4
α=0.98
α/2=0.49
We have to find the z value for the p value 0.49 which is z=2.33
Margin of error=z*μ/
=2.33*19.5/
=0.82
lower level=mean -m
=19.5-0.82
=18.68
after rounding upto 1 decimal
=18.7
upper mean = mean+m
=19.5+0.82
=20.52
Hence the confidence interval for the usage of water is (18.7,20.52).
Learn more about margin of error at brainly.com/question/10218601
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The number of shelves stephen can make is approximately 27
<h3><u>Solution:</u></h3>
Given that Stephen makes wooden shelves for his room
Stephen wants to make the shelves 3/4 foot long
He starts with a board that is 20 feet long
To find: number of shelves he can make
So the number of shelves stephen can make can make is found out by dividing 20 feet long board by 3/4 foot long


So the number of shelves stephen can make is approximately 27
By working with the given linear equation we will see that:
a) n = (d + 2)/4
b)
- A 3-penny nail is_5/4_inches.
- A 6-penny nail is_2_inches.
- A 10-penny nail is_3_inches.
<h3>
How to solve the equation for n?</h3>
Here we have the linear equation:
d = 4n - 2
We want to solve it for n, it means that we need to isolate n in one side of the equation.
If we first add 2 in both sides of the equation, and then we divide both sides by 4, we will get:
d + 2 = 4n
(d + 2)/4 = n
That is the equation solved for n.
b) The penny size is d, and n is the length of the nail, then:
if d = 3, we have:
n = (3 + 2)/4 = 5/4
if d = 6, then:
n = (6 + 2)/4 = 2
if d = 10, then:
n = (10 + 2)/4 = 3
Thus:
- A 3-penny nail is_5/4_inches.
- A 6-penny nail is_2_inches.
- A 10-penny nail is_3_inches.
if you want to learn more about linear equations:
brainly.com/question/1884491
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