Using the Central Limit Theorem, it is found that a sample size of 13 is needed.
In a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
It measures how many standard deviations the measure is from the mean. After finding the z-score, we look at the z-score table and find the p-value associated with this z-score, which is the percentile of X. By the Central Limit Theorem, the sampling distribution of sample means of size n has standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].For this problem, using a calculator:
The mean is [tex]\mu = 37.9[/tex]The standard deviation is [tex]\sigma = 14.07[/tex]The sample size needed is n when [tex]s = 4[/tex], as by the Empirical Rule, 95% of the measures are within 2 standard errors of the mean, hence [tex]2s = 8 \rightarrow s = 4[/tex]
[tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
[tex]4 = \frac{14.07}{\sqrt{n}}[/tex]
[tex]4\sqrt{n} = 14.07[/tex]
[tex]\sqrt{n} = \frac{14.07}{4}[/tex]
[tex](\sqrt{n})^2 = \left(\frac{14.07}{4}\right)^2[/tex]
[tex]n = 12.37[/tex]
Rounding up, a sample size of 13 is needed.
A similar problem is given at https://brainly.com/question/24663213
A population of bacteria is initially 2,000. After three hours the population is 1,000.
Assuming this rate of decay continues, find the exponential function that represents the size of the bacteria population after t hours. Write your answer in the form f(t)=a(b)t. Report numbers as fractions when necessary, or if using decimals, round to four decimal places.
The population starts at 2000, so a=2000.
We also know that the population in 3 hours is 1000, so we can setup the equation:
2000 b^3 = 1000
This gets us:
b^3 = 1/2
And taking the cube root of both sides gives us:
b ≈ 0.7937005259841
Rounding that to 4 places, we have:
f(t) = 2000 (0.7937)^t
Review:
Match each decimal with its equivalent simplified fraction.
NOTE: Simplified fractions may be in the improper fraction format.
0.25
[Choose]
0.14
[Choose ]
1.4
[Choose ]
0.4
[Choose ]
0.375
[Choose ]
Answer:
0.25-1/4
0.14-7/50
1.4-7/5
0.4-2/5
0.375-3/8
What is the cost of 4 pounds of apples, if 3 pounds of apples cost $5.28 and the unit price for each pound of apples is the same? *
10 points
A $6.28
B $7.04
C $12.32
D $7.40
Help please:)
Answer:
B. $7.04
Step-by-step explanation:
5.28 / 3 = 1.76
1.76 x 4 = 7.04
emily ran 3 3/4 miles in 5 hours what unit rate for miles per hour did she run
Answer: The answer is 3
Step-by-step explanation:
:]
A recipe calls for 2 cups of sugar for each 5 cups of flour. How many cups of sugar needed for 15 cups of flour?
Answer:
6 cups of sugar
Step-by-step explanation:
2/5=x/15
x=6
Help help help help help help math sucks help
Please check the mcq in the following picture and thank you
Answer 2nd one
Step-by-step explanation:
A family buys airline tickets online. Each ticket costs $208. The family buys travel
insurance with each ticket that costs $16 per ticket. The web site charges a fee of
$22 for the entire purchase. The family is charged a total of $1142. How many
tickets did the family buy
Answer:
5 tickets
Step-by-step explanation:
Each ticket costs $224 including the travel insurance and they are charged $22 regardless of the number of tickets they buy.
Therefore, the equation is 224x + 22 = 1142
First, you have to subtract the 22 from both sides to amount to 224x = 1120
Now, you divide 224 from 1120 to get 5
The family bought 5 tickets.
mark is paid $12.45 and hour at his job.he works a shift of 4 hours and 20minutes. how much does john earn for this shift?
Answer:
$53.95
Step-by-step explanation:
[Setting up an equation] 12.45x = y
() x is time worked and y is money made
[Plugging-in time worked] 12.45(4 [tex]\frac{1}{3}[/tex]) = y
[Multiply] 53.95 = y
[Answer] y = $53.95
Have a nice day!
I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)
- Heather
Write a recursive formula for An, the nth term of the sequence 80, -20,5, ....
Answer:
a[1] = 80; a[n] = -a[n-1]/4
Step-by-step explanation:
The given sequence has a first term of 80 and a common ratio of -20/80 = -1/4. That is, each term is -1/4 times the previous one. The recursive formula is ...
[tex]A_1=80\\A_{n}=-\dfrac{1}{4}\times A_{n-1}[/tex]
someone please help me on this anyone pls no link :(
9514 1404 393
Answer:
The correct answer is marked. (8·3)
Step-by-step explanation:
The order of operations requires that you start with by evaluating expressions in parentheses. Within parentheses, the order of operations applies, so you need to do multiplication before addition.
In this expression, the multiplication operation inside the parentheses is performed first. That is, you first compute 8·3.
_____
Additional comment
After that, you do the subtraction, to get ...
11 ÷ (-12) +2⁴
Then the exponential term is evaluated, and you have ...
11 ÷ (-12) +16
The division will result in a fraction, making it ...
(-11/12) +16
And, finally, the addition gives you ...
15 1/12
A
Triangle ABC is right-angled at A, and AD is the altitude from A to the hypotenuse BC.
Find x
Answer:
Step-by-step explanation:
5 x 6:30
Please help me ASAP this has limited time olease
Answer:
x= 67
Step-by-step explanation:
Angle CGE makes a 23 degree angle, and makes a 90 degree angle with CGB.
By subtracting 90 and 23, you get 67 degrees for the angle EGB.
Since angle EGB and angle AGF are vertical angles, they are the same. So, x would equal 67.
Answer:
x = 67°
Step-by-step explanation:
Solving for x
We know that AGC is a right angle, thus AGD has to be a right triangle as well. Angle CGE is 23°, which would mean that FGD is also 23°.
90°-23°=67°
6.2 Margin of error and the confidence interval. A study of stress on the campus of your university using the College Undergraduate Stress Scale (CUSS) reported an average stress level of 1123 (a higher score indicating more stress) with a margin of error of 43 for 95% confidence. The study was based on a random sample of 400 undergraduates. a. Give the 95% confidence interval. b. If you wanted 99% confidence for the same study, would your margin of error be greater than, equal to, or less than 43
Using confidence interval concepts, it is found that:
a. The 95% confidence interval is (1080, 1166).
b. The margin of error would be greater than 43.
Item a:
The interval is the sample mean plus/minus the margin of error, hence:
[tex]1123 - 43 = 1080[/tex]
[tex]1123 + 43 = 1166[/tex]
The 95% confidence interval is (1080, 1166).
Item b:
The margin of error is direct proportional to the critical value.The higher the confidence level, the higher the critical value, and thus, the higher the margin of error.Hence: The margin of error would be greater than 43.
A similar problem is given at https://brainly.com/question/25675821
Can someone please help me with this? I will give brainlist :(
Answer:
2nd
Step-by-step explanation:
The second one
Determine the greatest common factor of the numbers 24 and 56
Answer:
8
Step-by-step explanation:
yw :)
What is the value of x in the solution to this system of equations?
y = x + 1
y = 5x + 13
Step-by-step explanation:
y=x+1
y=5x+13
=13x/1
=5x/x
What is the answer to this question?
Answer:
The answer should be A.
Step-by-step explanation:
Timmy has a total of 15 dimes and nickles i his pocket. He has 7 more dimes than nickels. How many dimes does he have.
Answer:
1.98 I think sorry if it's wrong
50 points + brainliest answer questions 7 and 8 with work and all
Answer:
7) m∠BHE = 146°
8) m∠BAC = 25°
Step-by-step explanation:
Question 7:Given that, [tex]\displaystyle\mathsf{\overline{CD}\:||\:\overline{EF}}[/tex], and that [tex]\displaystyle\mathsf{\overline{AB}}[/tex] is a transveral.
We are also provided with the following measures of the angles: m∠DGH = 2x, and m∠FHB = 5x - 51.
∠DGH and ∠FHB are also corresponding angles, as they have corresponding positions on the same side of the transversal, [tex]\displaystyle\mathsf{\overline{AB}}[/tex]. These two angles also have the same measure.
Solve for x:In order to find the measure of ∠BHE, we could set up an equality statement on ∠DGH and ∠FHB to solve for the value of x.
m∠DGH = m∠FHB
2x = 5x - 51
Add 51 and subtract 2x from both sides of the equation:
2x -2x + 51 = 5x - 2x - 51 + 51
51 = 3x
Divide both sides by 3:
[tex]\displaystyle\mathsf{\frac{51}{3}\:=\:\frac{3x}{3}}[/tex]
x = 17
⇒ m∠DGH = 2x = 2(17) = 34°,
⇒ m∠FHB = 5x - 51 = 5(17) - 51 = 34°.
Since ∠FHB and ∠BHE are supplements (whose sum add up to 180°), we could determine the measure of ∠BHE as follows:
m∠BHE + m∠FHB = 180°
m∠BHE + 34° = 180°
m∠BHE + 34°- 34° = 180°- 34°
m∠BHE = 146°.
Therefore, the measure of ∠BHE is 146°.
Question 8:Given that ΔABC with [tex]\displaystyle\mathsf{\overline{AC}}[/tex] extended to D, and that m∠ABC = 63° and m∠BCD = 92°:
The Exterior Angle Theorem states that the measure of an exterior angle of a triangle is equal to the sum of the two nonadjacent interior angles. In other words: ∠BCD = ∠BAC + ∠ABC.
Before we could apply the Exterior Angle Theorem, we must first find m∠BAC. Since ∠BCD and ∠BCA are supplements:
m∠BCD + m∠BCA = 180°
92° + m∠BCA = 180°
92° - 92°+ m∠BCA = 180° - 92°
m∠BCA = 88°
Solve for m∠BAC:Now that we have the measure for ∠BCA, we can find m∠BAC by applying the Triangle Sum Theorem where it states that the sum of the interior angles of a triangle is equal to 180°.
m∠BCD + m∠ABC + m∠BAC = 180°
92° + 63° + m∠BAC = 180°
125° + m∠BAC = 180°
155° - 155° + m∠BAC = 180° - 155°
m∠BAC = 25°
Therefore, the measure of ∠BAC is 25°.
What is the average rate of change of the functionf (x) = 20(1/4)^xfrom x = 1 to x = 2?
Step-by-step explanation:
the average rate of change of a function f(x) between two values of x is
(f(x2) - f(x1)) / (x2 - x1)
f(x) = 20× (1/4)^x
x1 = 1
x2 = 2
f(x2) = 20× (1/4)² = 20/16 = 5/4
f(x1) = 20× (1/4)¹ = 20/4 = 5
(5/4 - 5) / (2 - 1) = (5/4 - 20/4) / 1 = -15/4
the average rate of change is -15/4.
A triangle has an angle that measures 60°. The other two angles are in a ratio of 3:5. What are the measures of those two angles?
Answer:
180
Step-by-step explanation:
all 3 angles of all triangles sum to 180
if one angle = 60, the other two angles sum to 120
a 3:5 ratio means one angle is 3/8 of 120 and the other is 5/8 of 120
3/8 times 120 = 3(120)/8 = 3(15)= 45 degrees
5/8 times 120 = 5(120)/8 = 5(15) = 75 degrees
45+75 = 120
120+60 = 180 degrees = sum of all 3 angles
in case you need an explanation and can I be get brainlest?
in a box of chocolate 1/5 are plain chocolate 1/3 are white chocolate the rest are white
...ok and?
finish the question
Answer:
Step-by-step explanation:
[tex]\frac{1}{5}+\frac{1}{3}+x=1[/tex]
[tex]\frac{3}{15}+\frac{5}{15}+x=\frac{1.15}{15}[/tex]
[tex]\frac{8}{15} + x=\frac{15}{15}[/tex]
[tex]\frac{8}{15} - \frac{8}{15} + x=\frac{15}{15}-\frac{8}{15}[/tex]
[tex]x=\frac{7}{15}[/tex]
I think you are missing the question but I bet you are looking for the rest of chocolate in the box.
-6 10/9 divided by 6/5
Answer:
-160/27
Step-by-step explanation:
How do you find the answer for 30=6x+20
Answer:
5/4Step-by-step explanation:
How do you find the answer for 30=6x+20?
solve for x30 = 6x + 20
10 = 6x
x = 10/6
semplify5/4
------------------ check
30 = 6 * 10/6 + 20
30 = 10 + 20
30 = 30
the answer is good
Math
........................................................................
Answer:
i believe the and\swe is g because it is located within the boundaries of plane p but is on a line (not the green segments) that goes outside of plane p
Step-by-step explanation:
A garden table and a bench cost $907 combined. The garden table costs $43 less than the bench. What is the cost of the
bench?
907 - 43 = 864 / 2 = 432: 907 - 432 = 475
The garden table costs $432.
The bench costs $475.
475 + 432 = 907
I hope this helps! :)
domain for f(x) = -0.25(x − 4) 2 − 6
Answer:
The domain will be (-8,8), {x|x E R}
Step-by-step explanation:
The -8,8 has to be sideways on the right. Thats the answer.
You charge $1625 on your credit card that adds 8.2% intere don't make any payments, what will your balance be after 4 years compounded continuously?"
Answer:$2227.22
Step-by-step explanation: I answered your question in your comment. If its not right report it please.
A.CED.A Garnetta owned 2400 shares of Metropolitan Corporation at a price of $45.50. The stock split 4-for-3. How was Garnetta financially affected by the split
Garnetta will have 3,200 shares worth $ 34,125 each.
Given that Garnetta owned 2400 shares of Metropolitan Corporation at a price of $ 45.50, and the stock split 4-for-3, to determine how Garnetta was financially affected by the split the following calculation must be performed:
3 = 2400 4 = X 4 x 2400/3 = X 9600/3 = X 3200 = X (2400 x 45.50) / 3200 = X 109200/3200 = X 34.125 = X
Therefore, Garnetta will have 3,200 shares worth $ 34,125 each.
Learn more in https://brainly.com/question/13981349