Answer:
The minimum number of samples required is 487.
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 - 0.95}{2} = 0.025[/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 - 0.025 = 0.975[/tex], so Z = 1.96.
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.
Standard deviation 4.5 mg/L.
This means that [tex]\sigma = 4.5[/tex]
What is the minimum number of samples required to estimate today's level to within 0.4 mg/L with 95% confidence?
This is n for which M = 0.4. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]0.4 = 1.96\frac{4.5}{\sqrt{n}}[/tex]
[tex]0.4\sqrt{n} = 1.96*4.5[/tex]
[tex]\sqrt{n} = \frac{1.96*4.5}{0.4}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*4.5}{0.4})^2[/tex]
[tex]n = 486.2[/tex]
Rounding up
The minimum number of samples required is 487.
6. An electrician needs to repair a lamp on a wall whose height is 55 m. The lamp
is 11 m below the top most point. She uses a ladder to reach the lamp as shown
in the figure below. If the ladder is inclined at 60 degrees to the ground, what is the length of the
ladder?
Answer:
first one is correct
Step-by-step explanation:
Find the surface area of the regular pyramid
Greetings from Brazil!
[tex]4\dfrac{1}{2} =\dfrac{9}{2}[/tex]
[tex]Af1=\dfrac{b\cdot h}{2} \cdot 4\\\\\\Af1=\dfrac{\dfrac{9}{2} \cdot 4}{2} \cdot 4\\\\\\Af1=\dfrac{\dfrac{36}{2} }{2} \cdot 4\\\\\\Af1=\dfrac{18}{2} \cdot 4\\\\Af1=9\cdot 4\\\\Af1=36~m^2[/tex]
[tex]Af2=l^2\\\\Af2=(\dfrac{9}{2})^2\\\\\ Af2=\dfrac{81}{4}\\\\Af2=20,25~m^2[/tex]
[tex]At=Af1+Af2\\At=36+20,25\\At=56,25~m^2[/tex]
I hope I helped you! =)
question 4 please, im not sure
Answer:
X=9
Step-by-step explanation:
Well since its a vertical angle, vertical angles are equal Or congruent.
So they equal the same so technically
3x+8=35
Solve
x=9
Answer:
x=9°
vertically opposite Angles are equal therefore (3x+8°)=35°
then 3x=35-8
3x=27
x=9
Help me I don’t know the answer
Answer:
It is C and D :)
Step-by-step explanation:
Each input is multiplied by 2 to get the output which is why it is C. The coordinates are just the input as the X value and the output as the Y value, which is why it is also D.
Hope this helps can I have brainliest pls
Need help please???
Answer:
y= [tex]\frac{3}{5}x[/tex] [tex]-\frac{26}{5}[/tex]
Step-by-step explanation:
x₁ y₁ m= slope
(2, -4) point-slope equation: y - y₁ = m( x - x₁)
y-(-4) = [tex]\frac{3}{5}[/tex]( x - 2)
y + 4 = [tex]\frac{3}{5} x[/tex] - [tex]\frac{6}{5}[/tex]
y = [tex]\frac{3}{5}x[/tex] - [tex]\frac{6}{5}[/tex] - [tex]\frac{20}{5}[/tex]
y = [tex]\frac{3}{5} x[/tex] - [tex]\frac{26}{5}[/tex]
Parents wish to have $100,00 available for a child’s education. If the child is now 9 years old, how much money must be set aside at 6% compounded semiannually to meet their financial goal when the child is 18.
The amount that should be set aside is $____. (Round up to the nearest dollar.)
Answer:
$58,739.46 so $58,739
Step-by-step explanation:
I suspect you want $100,000 not $10000
A = P(1 + r/t)^nt
A = final amount
P = initial principal
r = interest rate
n = number of times the interest is applied per time period
t = number of time periods elapsed
number of time periods is 18-9 = 9
semiannual 2 makes n = 2
A = 100,000
P = ????
r = 0.06
n = 2
t = 2
I used to finance calculator app to find P = 58739.46
and double checked by using the formula to find A
A = P(1 + r/t)^nt
= 58739( 1 + 0.06/2)^(2(9))
= 58739.46( 1.03)^18
= 99999.9987
OR
A = P(1 + r/t)^nt solve for P
P = A/[(1 + r/t)^nt]
= 10000/[(1 + 0.06/2)^(2(9))]
= 100000 / [1.03^18]
= $58,739.46
Two processes in a manufacturing line are performed manually: operation A and operation B. A random sample of 50 different assemblies using operation A shows that the sample average time per assembly is 8.05 minutes, with a population standard deviation of 1.36 minutes. A random sample of 38 different assemblies using operation B shows that the sample average time per assembly is 7.26 minutes, with a population standard deviation of 1.06 minutes.
Required:
For α = 0.10, is there enough evidence in these samples to declare that operation A takes significantly longer to perform than operation B?
Answer:
3.06
Step-by-step explanation:
The correct answer is - 3.06
Reason -
For sample A :
mean, [tex]\bar{x_{1} }[/tex] = 8.05
Standard deviation, [tex]\sigma_{1}[/tex] = 1.36
Size, [tex]n_{1}[/tex] = 50
For sample B :
mean, [tex]\bar{x_{2} }[/tex] = 7.26
Standard deviation, [tex]\sigma_{2}[/tex] = 1.06
Size, [tex]n_{2}[/tex] = 38
Now,
[tex]\bar{x_{1} }[/tex] - [tex]\bar{x_{2} }[/tex] = 8.05 - 7.26 = 0.79
Standard deviation error, SE = √([tex]\sigma_{1}[/tex]²/[tex]n_{1}[/tex] + [tex]\sigma_{2}[/tex]²/[tex]n_{2}[/tex]) = 0.2580
Now,
Z-statistic = ([tex]\bar{x_{1} }[/tex] - [tex]\bar{x_{2} }[/tex] )/ SE
= 0.79/0.2580
= 3.06
⇒Z-statistic = 3.06
The area of a rectangle is 42 square meters. The length is 7 meters. What is the width?
An equilateral triangle has side length 8 units. What is the area?
A. 24√3 units
B. 24 units
C. 32 units
D. 16√3 units
Answer:
D. 16√3
Step-by-step explanation:
To find the area, you have to find the height. To find that, you spit the triangle in half for a 30 - 60 - 90 triangle and figure out that the height is 4√3.
After you find the height, you do the equation for the area of a triangle which is 1/2 side * height, and you fill it out.
1/2 8 * 4√3
4 * 4√3
16√3
Will this be 1,3? so confused
Answer: yes the answer is (1,3) :)
Step-by-step explanation: you go by the horizontal axis (left to right) which is 1 and then the vertical axis (up and down) which is 3. the point of intersection is (1,3) hope this helps :) also don’t go to the link that the person posted, it might be dangerous.
What is the measure of angle x?
108°
43°
29
A. None of these
B. 43°
C. 29°
D. 108
Answer:
IF THERE IS A LINK DON'T CLICK ON IT
Step-by-step explanation:
IT'S A COMPUTER PHONE AND TABLET VIRUS
HELP ASAP PLEASE
What’s the answer
Answer:
Step-by-step explanation:
function 2
how many outfits can you make out of 2 helmets, 6 shirts, and 2 pairs of shorts
Answer:
2 OUTFITS
Step-by-step explanation:
Solve by Graphing: Y=4x-3 and y=-x+2
PLEASE LOOK AT PICURE THEN ANWSER, WHOEVER IS CORRECT I WILL MARK BRAINIEST :)
What is the volume of the rectangular prism?
3 cm
3 cm
3 cm
Answer:
Step-by-step explanation:
The volume of a cube is s^3
s = 3
Volume = 3*3*3
Volume = 27 cm^3
The average of 8, 14, and x is 10. What is the value ofx ?
O 8
O 10
O 11
O 12
Answer: so are you saying that 8+14x because I don’t know what you write so here the answer
Step-by-step explanation: Hope this help :D
Evaluate for x=10
8+(14)(10)
8+(14)(10)
=148
But if you don’t want that then I will guess the answer is C.11
The value of x is 8
Given: 8, 14, x
Average = 10
Then,
(8 + 14 + x) / 3 = 10
Cross product
(8 + 14 + x) = 3 × 10
22 + x = 30
x = 30 - 22
x = 8
Read more:
https://brainly.com/question/13158712
myq-eimh-otm
a.l.l
a.l.o.u.l.d
Need help thanks don’t understand
Answer:
You need help with what-?
An artist is commissioned to build two hollow glass sculptures standing vertically, one in the form of a triangular prism and one in the form of a rectangular prism. Their dimensions are shown below.
Please don’t answer just for points this is a milestones challenge and I actually need help :)
Answer: read below
Step-by-step explanation:
A. The volume of sculpture 1 is greater than the volume of sculpture 2. TRUE
B. The surface area of sculpture 2 is less than the surface area of sculpture 1. FALSE
C. The base of sculpture 1 covers a larger area than the base of sculpture 2. TRUE
D. Sculpture 1 requires more glass to complete than sculpture 2. FALSE
Please help me with this ASAP ASAP please please help
Step-by-step explanation:
The lateral area is formula for a cylinder is
[tex]2\pi \times r \times h[/tex]
where r is radius and h is height.
[tex]2\pi \times 8 \times 3 = 48\pi[/tex]
The surface area of cylinder is
[tex]2\pi \times {r}^{2} + 2\pi \times r \times h[/tex]
[tex]2\pi(64) + 2\pi(24)[/tex]
[tex]128\pi + 48\pi[/tex]
[tex]176\pi[/tex]
Volume of cylinder is
[tex]\pi \times {r}^{2} \times h[/tex]
[tex]\pi \times 64 \times 3[/tex]
[tex]192\pi[/tex]
Answer:
Step-by-step explanation:
Lateral area is the sides so for this it's distance around x 3 . b/c the cylinder is 3 units tall... sooo
r= radius , d= diameter
circumference = distance around = 2[tex]\pi[/tex]r or d[tex]\pi[/tex] = 16[tex]\pi[/tex]
Lateral area is 16[tex]\pi[/tex]*3 = 48[tex]\pi[/tex]
Surface area is the lateral area + the top and bottom
the area of a circle is [tex]\pi[/tex][tex]r^{2}[/tex]
the area of this circle for the top is [tex]\pi[/tex][tex]8^{2}[/tex]
64[tex]\pi[/tex]
times 2 b/c there is also a top and a bottom
128[tex]\pi[/tex] + 48[tex]\pi[/tex] = 176[tex]\pi[/tex]
surface area is 176[tex]\pi[/tex] [tex]units^{2}[/tex]
Volume of a cylinder is area of the circle base times the height.
the base is 64[tex]\pi[/tex]
time 3 = 192[tex]\pi[/tex] [tex]units^{3}[/tex]
Volume is 603.1857 [tex]units^{3}[/tex]
note that two of the answer include pi, but you have that already put in for you in the answer so leave that part off.
how many degrees is a acute angle
Any angle that measures less than 90 degrees
A college administrator wanted to know if the proportion of students who request online classes, lab classes, or lecture classes was different at two different campuses. At each campus, the administrator took a random sample of 250 students and asked each student which type of class they preferred. The conditions for the appropriate test were verified, and the chi-square test statistic for the test was calculated to be 4.01 with an associated p-value of 0.1347. If the significance level of the test was alpha = .05, what conclusion should the college administrator make about the proportion of students who request online classes, lab classes, or lecture classes at two different campuses?
A. There is convincing statistical evidence to suggest that the proportion of students who request certain classes is the same at each campus.
B. There is convincing statistical evidence to suggest that the proportion of students who request certain classes is different at each campus.
C. There is not convincing statistical evidence to suggest that the proportion of students who request certain classes is the same at each campus.
D. There is not convincing statistical evidence to suggest that the proportion of students who request certain classes is different at each campus.
E. There is not convincing statistical evidence to prove that the proportion of students who request certain classes is different at each campus.
Answer:
There is convincing statistical evidence to suggest that the proportion of students who request certain classes is the same at each campus. ( A )
Step-by-step explanation:
Given sample size = 250
Test statistic = 4.01
P-value = 0.1347
significance level = 0.05
while using chi-square we are supposed to reject H0, but we cant get the critical value ( Z - value ) because the information isn't available , but we are left with the P-value and this P-value been very low shows that the Alternate hypothesis is not strong enough for us to reject the Null hypothesis.
hence we will accept the Null Hypothesis
Answer: B. There is not convincing statistical evidence to suggest that the proportion of students who request certain classes is different at each campus.
Step-by-step explanation: The null hypothesis is that the proportion of students who request certain classes is the same at each campus. Since the p-value is greater than a, there is insufficient evidence to reject the null hypothesis and conclude the alternative hypothesis, that the proportion of students who request certain classes is different at each campus.
PLEASE ANSWER ASAP FOR BRAINLEST!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
You ask the students in class two questions. Which question is statistical and which is non-statistical? Explain.
What time does the first period begin?
What time do you leave home to go to school?
Answer:
the first is non-statistical and the second one is statistical
Step-by-step explanation:
when it is statistical it is asking in general (like a yes or no question) and when it's non-statistical it is asking something specific.
The figure is the net for a rectangular prism. What is the surface area of the rectangular prism represented by the net?
Answer:
Solution given:
net surface area=9×(3+5+3+5)+2(3×5)=174in² is your answer.
TSA
2(LB+BH+LH)2(5×3+3×9+5×9)2(15+27+45)2(42+45)2(87)174in²an expression is shown. 9,537 ÷ 33 what is the value of the expresion?
Answer:
9537÷33=289
why?
33×289=9537
How many tons are equal to 6,000 pounds
Answer:
6,000 Pounds =
3 Tons
Step-by-step explanation:
A pound is a unit of weight commonly used in the United States and the British commonwealths. A pound is defined as exactly 0.45359237 kilograms.
A ton, also referred to as a short ton, is a unit of weight equal to 2,000 pounds. It is commonly used in the United States. Most other countries use the metric ton, or "tonne".
There are 4 points that form a rectangle. Three of the points are: (-5 -1) (-5 3) (2<3 What are the coordinates of the fourth point?
Answer:
[tex]C = (2,-1)[/tex]
Step-by-step explanation:
Given
[tex]A = (-5,-1)[/tex]
[tex]B = (-5,3)[/tex]
[tex]D = (2,3)[/tex]
Required
The coordinate of the fourth point (C)
The given coordinates indicate the rectangle is vertical/horizontal because it has similar x and y values.
The coordinate of such rectangle can be represented as:
[tex]A = (x_1,y_1)[/tex]
[tex]B = (x_1,y_2)[/tex]
[tex]C = (x_2,y_1)[/tex]
[tex]D = (x_2,y_2)[/tex]
By comparing the general coordinates with the given coordinates, we have:
[tex]x_1 = -5[/tex] --- see A and B
[tex]y_1 = -1[/tex] --- see A and C
[tex]x_2 = 2[/tex] ---- see C and D
[tex]y_2 = 3[/tex] --- see B and D
So, we have:
[tex]C = (x_2,y_1)[/tex]
[tex]C = (2,-1)[/tex]
Answer is:
C. (2, -1)
The sum of two numbers is 802, and the difference of the 2 numbers is
438. What are the two numbers?
Answer:
x = 620
y = 182
Step-by-step explanation:
The sum of two numbers is 802
x + y = 802
The difference of two numbers is 438
x - y = 438
x + y = 802
x - y = 438 Add
2x = 1240 Divide by 2
x = 1240/2
x = 620
x + y = 802
620 + y = 802 Subtract 620 from both sides
y = 802 - 620
y = 182
John has an annual salary of $48,000.00 and he is paid every two weeks. What will his
gross income be on each paycheck?
Answer: $1846
Step-by-step explanation:
First and foremost, we should note that there are 52 weeks in a year. Therefore the biweekly payment of John will be gotten by dividing his gross income by 26 weeks i.e (52weeks/2) since it's biweekly.
Therefore, the gross income on each paycheck will be:
= $48,000.00 / 26
= $1846.15
= $1846 approximately
The gross income on each paycheck is $1846.