Answer:
A sample of 179 is needed.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.85}{2} = 0.075[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.075 = 0.925[/tex], so Z = 1.44.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
A previous study found that for an average family the variance is 1.69 gallon?
This means that [tex]\sigma = \sqrt{1.69} = 1.3[/tex]
If they are using a 85% level of confidence, how large of a sample is required to estimate the mean usage of water?
A sample of n is needed, and n is found for M = 0.14. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]0.14 = 1.44\frac{1.3}{\sqrt{n}}[/tex]
[tex]0.14\sqrt{n} = 1.44*1.3[/tex]
[tex]\sqrt{n} = \frac{1.44*1.3}{0.14}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.44*1.3}{0.14})^2[/tex]
[tex]n = 178.8[/tex]
Rounding up
A sample of 179 is needed.
A. Find the volume of a rectangular room measuring 22.75 ft. x 30 ft. x 14 ft.
B. Find the BTUs needed for that room if it faces South with poor insulation.
Help asap
Answer:
12 BTU
Step-by-step explanation:
Tom has seven blue Margaret Benny has four blue how many blue mop with two they have in all
Answer:
11
Step-by-step explanation:
Answer:
11
Step-by-step explanation:
7+4=11
Tom has 2 1/2 times as many cards as Harry. Together they have 98 cards. How many cards do they each have?
Answer:
Tom has 70 cards, and Harry has 28 cards.
Step-by-step explanation:
Let h = number of cards Harry has.
Then the number of cards Tom has is 2 1/2 * h = 2.5h.
Together they have 2.5h + h = 3.5h number of cards.
Together they have 98 cards.
3.5h = 98
h = 98/3.5
h = 28
Harry has 28 cards.
Tom has 2.5h = 2.5 * 28 = 70
Answer: Tom has 70 cards, and Harry has 28 cards.
Use inverse trigonometric functions to solve each problem.
A flag pole 30 feet tall casts a shadow of 50 feet on the ground. Find,
to the nearest tenth of a degree, the angle of elevation of the sun.
a.30°
b.31°
c.60°
d.61°
Answer:
BBBBBBBBBB
Step-by-step explanation:
Mensualmente el número de árboles talados aumenta en un 9% respecto del mes anterior. Si este mes hay 85.000 árboles talados, ¿cuántos árboles talados habrá, aproximadamente, en 6 meses más?
Answer:
FV= 639.483 arboles
Step-by-step explanation:
Dada la siguiente información:
Cantidad de árboles talados (A)= 85.000
Proporción de crecimiento (g)= 9% mensual
Cantidad de meses (n)= 6
Para calcular el total de árboles talados en 6 meses, tenemos que usar la siguiente formula:
FV= {A*[(1+i)^n - 1]} / i
A= cantidad de árboles talados
i= proporcion de crecimiento
n= cantidad de meses
FV= {85.000*[(1.09^6) - 1]} / 0.09
FV= 639.483 arboles
Ahora, la cantidad de árboles que se talaran en el sexto mes:
FV= PV*(1+i)^n
FV= 85,000*(1.09^6)
FV= 142.553
Can someone help me!
Answer:
m∠A = 48.81°
Step-by-step explanation:
Given triangle is a right triangle and we have to measure ∠A.
Since, opposite side and adjacent sides of angle A has been given
So we will apply tangent rule to get the measure of angle A.
tan(∠A) = [tex]\frac{\text{Opposite side}}{\text{Adjacent side}}[/tex]
tan(∠A) = [tex]\frac{8}{7}[/tex]
∠A = [tex]\text{tan}^{-1}(\frac{8}{7})[/tex]
∠A = 48.814
≈ 48.81°
Please help me. There are 25 students in Mrs. Benatar‘s class at the beginning of the school year, and the average number of siblings for each student is three. A new student with eight siblings join the class in November. What is the new class average for number of siblings? Round your answer to the nearest hundredth.
Answer: 3.19
Step-by-step explanation:
So to find the average I used a simple but pretty effective method
3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3+8/26=3.1923
So the new average is 3.19
I NEED HELP ASAP PLEASEEEE!!!!! Given the cube, what is the total surface area and volume?
Answer:
864
Step-by-step explanation:
144x6
Answer:
b
Step-by-step explanation:
depressed ppl say here
here
hehbsheheuehebdbd
Answer:
lol are you depressed ..........
The cheerleaders are making a banner that is 8 feet wide the length of the banner is 1 1/3 times the width of the banner how long is the banner
Answer:10 2/3 feet
Step-by-step explanation: 8 times 4/3= 32/3=10 2/3 feet
Which expression is equivalent to xy^2/9?
9514 1404 393
Answer:
the correct answer is marked
Step-by-step explanation:
The denominator of a fractional exponent becomes the index of the radical when the power is written using a radical. The fractional power only applies to the y-factor, so that is all that is under the radical.
[tex]\displaystyle xy^{\frac{2}{9}}=x\cdot (y^2)^{\frac{1}{9}}=\boxed{x\sqrt[9]{y^2}}[/tex]
2 Easy 7th Grade questions but its due in 7 min HELP ASAP
A cylinder-shaped beaker is 6 inches tall and its base measures 4 inches across. For a science experiment, Gloria must fill 1/3 of the beaker with water. How much water will Gloria use for the experiment?
What is the height of the cone if the volume is 12 pie ft ? And radius is 3ft
Answer:
Step-by-step explanation:
Problem One
V = pi r^2 h
V = 3.14 * (4/2)^2 * 6
V = 3.14 * 4 * 6
V = 75.36
However, that is not the answer. The answer is 1/3 of that amount.
V1 = 1/3 * 75.36
V1 = 25.12
Problem 2
V= `12 pi
r = 3 feet
Formula
V = 1/3 pi r^2 h
12* pi = 1/3 * pi * 3^2 * h Cancel the pi s.
12 = 1/3 * 9 * h
12 = 3 h Divide by 3
12/3 = h
h = 4
What’s the volume of the rectangular prism of 2cm, 7/3 cm and 2cm?
Answer:
9 1/3 cm³
Step-by-step explanation:
First multiply two numbers.
2x2=4
Then multiply the product by the third number.
4x7/3
4 x 7
1 x 3
= 28/3 or 9 1/3
--
hope it helps
Marie spent $15 on 4 identical jars of jelly. Each jar of jelly costs the same amount. How much did 1 jar of jelly cost? Use paper to show your work.
One jar of jelly costs $
Answer: $3.75
Step-by-step explanation:
First you would have to find the unit rate.
$15 / 4 jars of jelly = $3.75
Therefore, 1 jar of jelly = $3.75
Answer:
the answer is $3.75
Step-by-step explanation:
15 ÷ 4= 3.75
to verify your answer multiply
3.75 × 4= 15
What is the median value of the data set shown on the line plot?
Enter your answer in the box.
[_]
Answer:
6 is the median...
Step-by-step explanation:
Well first off, you need to know what a median is.
Let's break down the root/suffix/prefix.
Med= Meduim/middle
Median means the middle value.
Let's look at our data:
Skip zero
1-1- First
2-1- second
3-2-third
4-2-forth
5-3 fifth
6-4 - Six is in the middle of the line, making it the median.
7-3 seventh
8-3 eighth
9-2 ninth
10- 0 tenth
11-1 eleventh
12-0 twelfth
What's in between 1-12? 6!!! There's our answer!!!
I hope this helped you! Have a great day!!!
5. Find the surface area of a sphere with
the radius of 1.5 cm.
a. 28.26 cm
b. 7.065 cm
c. 18.84 cm
d. 14.13 cm
Draw a square that has (-2,4) and (3,-1) as two of its vertices
Answer:
square with (-2,4) and (3,-1) vertices
o put on Your Thinking Cap!
$ Challenging Practice
1.
Michelle got an average score of 80 on two tests. What score must
she get on the third test so that her average score for the three tests
is the same as the average score for the first two tests?
Answer:
Michelle must get an 80 on her next test to keep her average score.
Step-by-step explanation:
Since Michelle got an average score of 80 on two tests, to determine what score she must get on the third test so that her average score for the three tests is the same as the average score for the first two tests, the following calculation must be performed:
X / 2 = 80
X = 80 x 2
X = 160
X x 3 = 80 x 3
X x 3 = 240
X = 240/3
x = 80
So, Michelle must get an 80 on her next test to keep her average score.
A CD has a diamter of 4.75 inches, Find the circumference, Use calculator pi or 3.14. Round to the nearest hundredth, if necessary.
WILL GIVE BRAINLIEST!!!
Answer:
15 in.
Step-by-step explanation:
A school district is considering moving the start of the school day at Groveland High from 8:00 a.m. to 9:00 a.m. to allow students to get more sleep at night. They want to estimate how many more hours of sleep teens get if their school starts at 9:00 a.m. compared to teens whose schools start at 8:00 a.m. The district takes random samples of 50 of students from Groveland High and 39 students from Phillips High School, which starts at 9:00 a.m., and surveys them about their sleep habits. The sample mean number of hours of sleep per student at Groveland is 7.1 hours, and the standard deviation is 1.7 hours. At Phillips, the sample mean is 8.3 hours of sleep, with a standard deviation of 1.9 hours. What is the 90% confidence interval for the difference in mean hours of sleep for students at the two high schools
Answer:
The answer is "[tex]\bold{(7.1-8.3) \pm 1.665 \sqrt{\frac{(1.7)^2}{50}+\frac{(1.9)^2}{39}} }\\\\[/tex]"
Step-by-step explanation:
Given values:
[tex]\bar{x_1}=7.1\\\\\bar{x_2}=8.3\\\\s_1=1.7\\\\s_2=1.9\\\\n_1=50\\\\n_2=39[/tex]
Using formula:
[tex]\to (\bar{x_1} -\bar{x_2}) \pm t \sqrt{\frac{(s_1)^2}{n_1}+\frac{(s_1)^2}{n_2}} \\\\[/tex]
Put the values in the above formula:
[tex]\to (7.1-8.3) \pm 1.665 \sqrt{\frac{(1.7)^2}{50}+\frac{(1.9)^2}{39}} \\\\[/tex]
The cost of one pen when pens are priced at 5 for p dollars
I really need help on this
Answer:
$1
Step-by-step explanation:
If 5 pens = $p, then 1 pen = $p/5.
But because 5 pens = $p, it would be the same thing as 5 = p because you just take off the labels.
So p = 5 and one pen would be:
$p/5 = 1
5/5 = 1
1 = 1
There is a 30% probability of
hail. What is the probability
that it will NOT hail?
Answer:
70% probability
Step-by-step explanation:
100% probability
-30% probability
=70% probability
I can't figure this problem out Please, I need some help.
Answer:
66
Step-by-step explanation:
solve for the missing side and round to the nearest tenths place
Answer:
A. 22.5
Step-by-step explanation:
Apply Trigonometric function.
Reference angle = 64°
Opposite side to 64° = x
Hypotenuse = 25
Apply SOH:
Sin 64 = Opp/Hyp
Sin 64 = x/25
25 × Sin 64 = x
22.4698512 = x
x = 22.5 (nearest tenth)
ASAP HELPPP NO LINKS! IF THIS IS A FALSE RESPONSE I AM REPORTING
A water cooler in the school office dispenses cone-shaped paper cups. The height of a cup is 5 inches and it has a radius of 2 inches. How many cubic inches of water will it take to fill up the paper cup? Round your answer the nearest hundredth.
Answer:
37.699 cubic inches of water
Step-by-step explanation:
Volume of a cone is V= 1/3 pi r^2 h
We are given that the height is 5 in and the radius is 2 in.
Plug that into the formula: V= 1/3 pi 2^2 9
1/3 x 4 x 9 = 12
Now we are left with 12 pi.
Use a calculator and multiply 12 by pi to get:
37.699
there are 6 rows of chairs 4 rows are empty
Answer:
then only 2 rows are full
Step-by-step explanation:
im confused but if thats it then thats the answer if im right mark me brainliest
:>
Graph the polynomial function,
f(x) = – x3 + 2x2
See attatched picture
5. In a right triangle, the sum of the lengths of the two legs is 100 meters. What are the lengths of the three sides
of this right triangle if the triangle's area is maxed out?
Answer:
6m by 8m by 10m
Step-by-step explanation:
6²+8²= 100
36+64=100
100=100
BRAINLIEST FOR CORRECT ANSWER, IM FAILING SCHOOL AND NEED HELP ASAP. EVEN OFFICIAL HELP COUNTS
Answer:
Verifal angles I think but I'm not necessarily sure!!!
determine if the work for each problem is correct correct only errors and explain your thinking
Answer:
v= BH
the second part is wrong the base is 7.5 not 9.5
so the base look like this
v = 7.5(13)
v = 97.5
Step-by-step explanation: