Answer:
x = 8 , y = 11
Step-by-step explanation:
[tex]2x + 2y = 38 => x + y = 19 - -- ( 1 ) \\\\y = x + 3 ---- ( 2 ) \\\\Substitute \ ( 2 ) \ in \ ( 1) :\\\\ x + y = 19\\\\x + ( x+ 3) = 19\\\\2x + 3 = 19\\\\2x = 19 - 3 \\\\2x = 16 \\\\x = \frac{16}{2} = 8\\\\Substitute \ x = 8 \ in \ ( 1 ) : \\\\x + y = 19\\\\8 + y = 19\\\\y = 19 - 8 = 11[/tex]
The survey included a random sample of 640 western residents and 540 northeastern residents. 39% of the western residents and 51% of the northeastern residents reported that they were completely satisfied with their local telephone service. Find the 99% confidence interval for the difference in two proportions
Answer:
The 99% confidence interval for the difference in two proportions is (0.0456, 0.1944).
Step-by-step explanation:
Before building the confidence interval, we need to understand the central limit theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Western residents:
39% out of 640, so:
[tex]p_1 = 0.39[/tex]
[tex]s_1 = \sqrt{\frac{0.39*0.61}{640}} = 0.0193[/tex]
Eastern residents:
51% out of 540, so:
[tex]p_2 = 0.51[/tex]
[tex]s_2 = \sqrt{\frac{0.51*0.49}{540}} = 0.0215[/tex]
Distribution of the difference:
[tex]p = p_2 - p_1 = 0.51 - 0.39 = 0.12[/tex]
[tex]s = \sqrt{s_2^2+s_1^2} = \sqrt{0.0215^2+0.0193^2} = 0.0289[/tex]
Confidence interval:
[tex]p \pm zs[/tex]
In which
z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
99% confidence level
So [tex]\alpha = 0.01[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].
The lower bound of the interval is:
[tex]p - zs = 0.12 - 2.575*0.0289 = 0.0456[/tex]
The upper bound of the interval is:
[tex]p + zs = 0.12 + 2.575*0.0289 = 0.1944[/tex]
The 99% confidence interval for the difference in two proportions is (0.0456, 0.1944).
Kendall wants to estimate the percentage of vegetarians who are also vegan. She surveys 150 vegetarians and finds that 45 are vegan. Find the margin of error for the confidence interval for the population proportion with a 95% confidence level.
Answer:
0.0733364
Step-by-step explanation:
Given :
Number of vegans = x ;
Sample size, n = 150
Zα/2 ; Zcritical at 95% = 1.96
p = x / n = 45 / 150 = 0.3
Margin of Error :
Zcritical * √(p(1 - p) / n)
1.96 * √(0.3(1 - 0.3) / 150)
Margin of Error :
1.96 * √(0.3 * 0.7) / 150)
1.96 * √0.0014
Margin of Error = 0.0733364
Pls help
Minni is arranging 3 different music CDs in a row on a shelf. Create a sample space for the arrangement of a jazz CD (J), a pop CD (P), and a rock CD (R).
Given:
Minni is arranging 3 different music CDs in a row on a shelf.
To find:
The sample space for the arrangement of a jazz CD (J), a pop CD (P), and a rock CD (R).
Solution:
We know that the total number of ways to arrange n items is n!.
Minni is arranging 3 different music CDs in a row on a shelf. So, the total number of ways is:
[tex]3!=3\times 2\times 1[/tex]
[tex]3!=6[/tex]
The sample space for the arrangement of a jazz CD (J), a pop CD (P), and a rock CD (R) is:
{JPR, JRP, PJR, PRJ, RJP, RPJ}
Therefore, the required sample space is {JPR, JRP, PJR, PRJ, RJP, RPJ}.
Answer:
RPJ, JPR, PRJ, JRP, RJP, JPR.
Step-by-step explanation:
What’s the distance between (4,-9) and (5,3)
Answer: Distance = √145
Concept:
Here, we need to know the concept of the distance formula.
The distance formula is the formula, which is used to find the distance between any two points.
If you are still confused, please refer to the attachment below for a clear version of the formula.
Solve:
Given information
(x₁, y₁) = (4, -9)
(x₂, y₂) = (5, 3)
Given formula
[tex]Distance = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]
Substitute values into the formula
[tex]Distance = \sqrt{(5-4)^2+(3+9)^2}[/tex]
Simplify values in the parentheses
[tex]Distance = \sqrt{(1)^2+(12)^2}[/tex]
Simplify exponents
[tex]Distance = \sqrt{1+144}[/tex]
Simplify by addition
[tex]Distance = \sqrt{145}[/tex]
Hope this helps!! :)
Please let me know if you have any questions
Answer:
[tex]\boxed {\boxed {\sf \sqrt {145} \ or \ 12.04}}[/tex]
Step-by-step explanation:
The distance between 2 points is calculated using the following formula.
[tex]d= \sqrt {(x_2-x_1)^2+(y_2-y_1)^2)[/tex]
In this formula, (x₁, y₁) and (x₂, y₂) are the coordinates of the two points.
We know the two points are (4, -9) and (5,3). If we match the values of the points and the coordinating variable, we see that:
x₁ = 4y₁= -9 x₂ = 5 y₂ = 3Substitute the values into the formula.
[tex]d= \sqrt { ( 5 -4)^2 + ( 3 --9)^2[/tex]
Solve inside the parentheses.
(5-4)= 1 (3 --9) = (3+9) = 12[tex]d= \sqrt {(1)^2 + (12)^2}[/tex]
Solve the exponents.
(1)² = 1 *1 = 1 (12)² = 12 * 12 = 144[tex]d= \sqrt{ 1+144}[/tex]
Add.
[tex]d= \sqrt{145[/tex]
Take the square root.
[tex]d=12.04159458[/tex]
Let's round to the nearest hundredth. The 1 in the thousandth place tells us to leave the 4 in the hundredth place.
[tex]d \approx 12.04[/tex]
The distance between the 2 points is √145 or approximately 12.04.
Select the expression that represents the following statement: 3 times one fourth the difference of 26 and 10.
one fourth x (26 + 10) x 3
one fourth x (26 − 10) x 3
3 x one fourth x 26 − 10
3 x one fourth x 26 x 10
PLEASEE HEPPP
Answer:
the second option #2
one fourth x (26-10) x 3
Step-by-step explanation:
Two of the options (#1 and #4) can be ruled out immediately since they don't involve the difference of 26 and 10.
#3 can be ruled out because the difference needs to be multiplied by one fourth, but this option gives the wrong answer since the multiplication is done before subtraction (BODMAS)
Answer:
c
Step-by-step explanation:
I got it correct on a quiz
The area of a circle is 144cm².Find the radius
Answer:
It's a decimal, so it's around 6.771cm
Step-by-step explanation:
First, divide 144cm² by pi, or 3.14. Then find the square root of the answer, giving you the radius. The formula for the area of a circle is pi x radius squared, so to find out the radius you just use this formula in reverse.
If I messed up or didn't make my explanation clear, please comment.
Answer:
radius is [tex]\frac{12}{\sqrt{\pi } }[/tex] = 6.77 cm
Step-by-step explanation:
we know,
[tex]\pi[/tex] × r² = Area
⇒ [tex]\pi[/tex] × r² = 144
⇒ r² =[tex]\frac{144}{\pi}[/tex]
⇒ r= [tex]\frac{12}{\sqrt{\pi } }[/tex]
∴ r= [tex]\frac{12}{\sqrt{\pi } }[/tex]
pls mark this as the braniliest
Economists predict that Americans will spend $1,180 on electonics in
2020. this is a 6.8% increase from last year. What did Americans spend
last year?
Is the following polynomial or not
5xy^2+3x^2y-2x^2y^2
9514 1404 393
Answer:
is a polynomial
Step-by-step explanation:
The expression is a sum of products.
Each product involves a numerical value and a product of variables to positive integer powers.
These meet the requirements for an expression to be a polynomial, so ...
the given expression is a polynomial
What is the largest product that can be made from whole numbers that add up to 100?
Answer:
Step 1: Find the largest product
50 + 50 = 100
50 * 50 = 2500
Answer: I believe that the largest product is 2500
Plz someone help me
Step-by-step explanation:
yo
so sorry I can't
really answer it
the average temperature at the south pole is -49.62and the average temperature at north pole is -34.68. how much higher is the average temperature at the north pole than at the south pole
The graph shows the distribution of the number of text messages young adults send per day. The distribution is approximately Normal, with a mean of 128 messages and a standard deviation of 30 messages.
What percentage of young adults send more than 158 text messages per day?
16%
34%
68%
84%
Answer:
You'd think its 34% but apparently it's 16%.
I hope this is right. If its not then it must be 34%.
(A) -- or maybe (B). 80% confident it is A.
ED2021
The polygons in each pair are similar. Find the missing side length.
Let missing one be x
If both are similar
[tex]\\ \sf\longmapsto \dfrac{20}{25}=\dfrac{16}{x}[/tex]
[tex]\\ \sf\longmapsto \dfrac{4}{5}=\dfrac{16}{x}[/tex]
[tex]\\ \sf\longmapsto 4x=16(5)[/tex]
[tex]\\ \sf\longmapsto x=\dfrac{16(5)}{4}[/tex]
[tex]\\ \sf\longmapsto x=20[/tex]
complete explanation
Answer:
[tex]x ^{m - 3} \div x^{m - 4} \\ \frac{ {x}^{m - 3} }{ {x}^{m - 4} } \\ \frac{ {x}^{m - 3 - m + 4} }{x} \\ \frac{ {x}^{1} }{x} \\ x \: and \: x \: will \: cancel \: each \: other \: hence \: answer \: will \: be \: 1[/tex]
._. Help me please I’m putting my faith in this app.
Find the missing side of the triangle
Answer:
x = 4[tex]\sqrt{2}[/tex]
Step-by-step explanation:
Pytago:
x[tex]x^{2} +7^{2} = 9^{2} \\\\x = \sqrt{9^{2} - 7^{2} } x = 4\sqrt{2}[/tex]
Determine what type of model best fits the given situation: A 4% raise in salary each year.
the models aren't given..
Answer: no models given
Step-by-step explanation:
Find the smallest possible value of x+y so that x^2 − y^2 is divisible by 74, where x and y are positive integers.
Answer: 2
Step-by-step explanation:
We know by different of squares, (x-y)(x+y)=74. Since we need to find the smallest possible answer for x+y, we let x+y=2, where both x and y = 1.
Elijah invested $ 830 in an account paying an interest rate of 4.9% compounded quarterly. Assuming no deposits or withdrawals are made, how much money, to the nearest cent, would be in the account after 13 years?
Answer:
$9986
Step-by-step explanation:
You got 13*4=52 quarters in 13 years.
Amount = 830*(1+0.049)^52
Amount = 9986.27
Urgent please I neeed some help !!!!!!!!!!!!!!!!!!!!!! URGENT 20 point bonus
Answer:
113.1
Step-by-step explanation:
use the formula to solve for volume
What are four ways an inequality can be written?
Answer:
There are four ways to represent an inequality: Equation notation, set notation, interval notation, and solution graph.
Integers that are not whole numbers
Answer:
a negative integer
Step-by-step explanation:
For f(x)=1/x^2-3, substitute h for x in the function to solve for f(h).
The required function of h i.e f(h) is expressed as
[tex]f(h) = \dfrac{1}{h^2-3}[/tex]
Substitution of a function means replacing a variable with another variable without changing the structure of such function. According to the function given, we can see that we are simply meant to replace x with h as shown below:
Given the expression
[tex]f(x) = \frac{1}{x^2-3}[/tex]
To get f(h), we will substitute f in place of x that is x -> h as shown
[tex]f(h) = \frac{1}{h^2-3}[/tex]
Hence the required function of h i.e f(h) is expressed as
[tex]f(h) = \dfrac{1}{h^2-3}[/tex]
Learn more: https://brainly.com/question/4357143
A clothing factory makes small, medium, and large sweaters. Last week, the factory made
1,612 sweaters. The factory made 3 times as many small sweaters as large sweaters. They
made 3 times as many medium sweaters as small sweaters.
How many small sweaters did the factory make last week?
This requires finding the number of small sweaters the company made last week
Number of small sweaters the company produced last week is 372
Total sweaters made = 1,612
Let
Small sweaters = 3x
Medium sweaters = x
Large sweaters = 3(3x) = 9x
Total = small + medium + large
1,612 = 3x + x + 9x
1612 = 13x
Divide by 13
x = 1612/13
Medium sweaters = x = 124
Small sweaters = 3x
= 3(124)
= 372
Read more:
https://brainly.com/question/24326559
Please help asap! Easy question :)
Two fair dice are rolled. Determine the following probability:
P(one number is a multiple of 4 and the other is a multiple of 6)
Answer:
P(one number is a multiple of 4 and the other is a multiple of 6) = 1/18
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
Total outcomes:
For the pair of dice:
(1,1), (1,2), (1,3), (1,4), (1,5), (1,6)
(2,1), (2,2), (2,3), (2,4), (2,5), (2,6)
(3,1), (3,2), (3,3), (3,4), (3,5), (3,6)
(4,1), (4,2), (4,3), (4,4), (4,5), (4,6)
(5,1), (5,2), (5,3), (5,4), (5,5), (5,6)
(6,1), (6,2), (6,3), (6,4), (6,5), (6,6)
So 36 total outcomes.
Desired outcomes:
One multiple of 4 and one multiple of 6.
2 possible outcomes: (4,6) or (6,4)
Probability:
2 outcomes out of 36, so:
[tex]p = \frac{2}{36} = \frac{1}{18}[/tex]
Then
P(one number is a multiple of 4 and the other is a multiple of 6) = 1/18
The bike you have been saving for is discounted 15%. You have $600 saved to purchase it. The original, non-discounted price of the bike is $650. There is a 5.58% sales tax added to the price of the bike. After you purchase the bike with the discount and sales tax, how much money will you have left over? Round your answer to the nearest dollar.
Answer:
16.67 or 17 when rounded to nearest dollar
Step-by-step explanation:
$650 x .85 (100%-15% discount) = 552.50 cost of bike on sale
552.50 x 1.0558 (100% + 5.58% tax) = 583.33 cost with tax added.
$600 - 583.33 = $16.67 money left over
The absolute value of a number is the _______
away from zero
on the number line. It is always positive because it refers to distance.
Answer:
Distince
I hope thats correct i have never been good at fill in da blanks
Answer:
test
Step-by-step explanation:
test
Please solve the equation 4X-25=71
d) A movie time was 2hours. 10% of the time was taken advertisement. How long was the actual movie?
Answer:
108 minutes
Step-by-step explanation:
Lets say that M+A is the time of the movie and the advertisement, so;
M+A = 2
And we know that 10% of that time is advertisement, mathematically that is:
A = 0,1*2
So replacing the second equation in the first one we have;
M + 0,1*2 = 2
M = 2-0,1*2 = 1,8 hours
We can convert hours into minutes multiplying by 60
1,8h*60min/h = 108min
6x47
Which multiple of 10 is closest to 47?
Answer:
50 is your answer:)Step-by-step explanation:
Answer:
50
Step-by-step explanation:
50 is the multiple of 10 that is closest to 47.
