Answer:
104
Step-by-step explanation:
x=4 ; y=3
7×2 +6xy+6y
7×2+6(4)(3)+6(3)
14+72+18
104
In order to estimate the average time spent per student on the computer terminals at a local university, data were collected for a sample of 81 business students over a one-week period. Assume the population standard deviation is 1.8 hours. If the sample mean is 9 hours, then the 95% confidence interval is
Answer:
(8.608, 9.392)
Step-by-step explanation:
We have the following information
Population standard deviation = 1.8
Sample mean = 9 hours
Sample n = 81
C I = 95%
So level of significance
Alpha = 1-0.95
= 0.05
Z critical at 0.05/2
Z(0.025) = 1.96
The 95% c.i =
9+-(1.96)(1.8/√81)
9+-(1.96)(0.2)
(9-0.392)(9+0.392)
(8.608, 9.392)
This is the confidence interval at 95%.
I hope you find my solution useful. Good luck!!!
Answer true or false and explain your answer. If it is important not to reject a true null hypothesis, the hypothesis test should be performed at a small significance level.
Answer: No, The goal when testing a hypothesis is to to guess a large significant level to possibly have the answer correct based upon evidence. False. It needs to be a large significant level
Step-by-step explanation:
A line has a slope of 9 and passes through the point (2, 8). What is its equation in slope-intercept form? Explain?
Answer:
y = 9x-10
Step-by-step explanation:
Slope-Intercept form is y = mx + b where m is the slope and b is the y intercept.
plug in what we are given
8 = 9(2) + b
solve for the y intercept (b)
8=18+b
8-18 = b
-10 = b
plug the slope (m) and y intercept (b) into our formula
y = 9x - 10
Mr. Mason’s class is going on a field trip. There are 27 students. There will be 1 adult for every 9 students. Mr. Mason wants to know how many adults (n) are needed for the field trip. Which of the following equations should he use?
A. 9n + 27
B. 27 – 9n
C. 9n = 27 - 1
D. 9n = 27
Answer:
D. 9n = 27
Step-by-step explanation:
If we need one adult for every 9 students, we can represent that as 9n:
if n is the number of adults.
Because we have 27 students, the equation 9n = 27 works.
A better way of formatting the equation is:
n = 27/9
Because it directly shows what the number of adults is, but with some reformatting, it is clearly the same equation.
A rectangular room is 6 meters longer than it is wide, and its perimeter is 28
meters. Find the dimension of the room.
Answer: width = 4 and length = 10
Step-by-step explanation:
Width = w and length = w + 6
2(w) + 2 (w + 6) = 28
2w + 2w + 12 = 28
4w = 28 - 12
W = 16/4
W = 4 (width)
Length = w + 6
4 + 6 = 10
Im new to this app!
And im looking for help!!
Please help ASAP!!!
Please!!!!
y=-4x²-8x+1
а<0 so we will be looking for maximum
х=-b/2a=8/-8=-1
у=4+8+1=13
Maximum point (-1;13)
A can of soda is placed inside a cooler. As the soda cools, its temperature T(x) in degrees Celsius is given by the following exponential function, where is the number of minutes since the can was placed in the cooler.
T(x)=-22+44e^-0.03x
Find the initial temperature of the soda and its temperature after 18 minutes.
Answer:
Ans: -21.87 ≅ -22°C
Step-by-step explanation:
T(x)=-22+44e^-0.03x
Initial temperature (x = 0):
T(0) = = -22 + 44e-0.03(0) = -22 + 44(1) = 22°C
After 18 minutes (x = 18):
T(18) = -22 + 44e-0.03(18) = -21.87°C ≅ -22°C
Need the answer plz.
on monday, sammy the storekeeper decided the increase the price of avocados by 20%. on tuesday he increases this price by another 25%. what percent of the original avocados after both increases? on Wednesday, sammy decides to return the avocados to their original price. by what percent must he decrease the tuesday price?
Answer:
I think 55%
Step-by-step explanation:
Answer:
Increases = 50%On Wednesday, sammy must decrease 50% to return to original priceStep-by-step explanation:
price on monday go to: 100% + 20% = 120% = 1,2 x first price
price on tuesday go to: 125% of 120% = 1,25 x 1,2 = 1,5 x first price
Increases = 50%
on Wednesday, sammy must decrease 50% (of price after second increases) to return to original price
For example for understanding:
If original price is $100
firs increase: new price: $100 + $20 = $120
second increase: new new price: $120 + $30 = $150
final price - original price = $150 - $100 = $50
And icreases/original = $50/$100 =0,5 = 50%
For return to orignial price, sammy must have to reduce 50% the price of avocados in wednesday
Find the surface area of a sphere
with a radius of 9 cm.
Surface Area = [?] cm?
Answer:
[tex] 1,017.36 \: {cm}^{2} [/tex]
Step-by-step explanation:
Surface area of a sphere
[tex] = 4\pi {r}^{2} \\ = 4 \times 3.14 {(6)}^{2} \\ = 12.56 \times 81 \\ = 1,017.36 \: {cm}^{2} [/tex]
Answer:
1017.36 cm²
Step-by-step explanation:
Given :-
Radius = 9cm .We know ,
SA = 4π r²SA = 4* 3.14 * (9cm)² SA = 4 *3.14*81cm²SA = 1017.36 cm²
oliver walks 5/8 of a mile in 1/6 of an hour. What is his unit rate in miles per hour?
Answer:
3.75 miles per hour
Step-by-step explanation:
(5/8)/(1/6)=3.75 mph, or you could do 5/8 x 6, since 1/6 x 6 equals one hour
Answer:
3 3/4 miles per hour
Step-by-step explanation:
Take the miles and divide by the hours
5/8 ÷ 1/6
Copy dot flip
5/8 * 6/1
Rewriting
5/1 * 6/8
5/1 * 3/4
15/4
3 3/4
A company is studying the number of monthly absences among its 125 employees. The following probability distribution shows the likelihood that people were absent 0, 1, 2, 3, 4, or 5 days last month.Number of days Absent | Probability 0 0.60 1 0.20 2 0.12 3 0.04 4 0.04 5 0.001. What is the mean number of days absent? What are the variance and standard deviation?2. For the following probability distribution: a) x|10|11|12|13|14b) P(x)|.1|.25|.3|.25|.13. Find the mean, variance and standard deviation for the following probability distribution.
Answer:
(1)
[tex]E(x) = 0.72[/tex]
[tex]Var(x) = 1.1616[/tex]
[tex]\sigma = 1.078[/tex]
(2)
[tex]E(x) = 12[/tex]
[tex]Var(x) = 1.3[/tex]
[tex]\sigma = 1.14[/tex]
Step-by-step explanation:
Solving (1):
[tex]\begin{array}{ccccccc}{Days} & {0} & {1} & {2} & {3} & {4}& {5} \ \\ {Probability} & {0.60} & {0.20} & {0.12} & {0.04} & {0.04} & {0.00} \ \end{array}[/tex]
(a): Mean
This is calculated as:
[tex]E(x) = \sum x * P(x)[/tex]
So, we have:
[tex]E(x) = 0 * 0.60 + 1 * 0.20 + 2 * 0.12 + 3 * 0.04 + 4 * 0.04 + 5 * 0.00[/tex]
[tex]E(x) = 0.72[/tex]
Solving (b): The variance
This is calculated as:
[tex]Var(x) = E(x^2) - (E(x))^2[/tex]
Where:
[tex]E(x) = 0.72[/tex]
and [tex]E(x^2) = \sum x^2 * P(x)[/tex]
So, we have:
[tex]E(x^2) = 0^2 * 0.60 + 1^2 * 0.20 + 2^2 * 0.12 + 3^2 * 0.04 + 4^2 * 0.04 + 5^2 * 0.00[/tex]
[tex]E(x^2) = 1.68[/tex]
So, we have:
[tex]Var(x) = E(x^2) - (E(x))^2[/tex]
[tex]Var(x) = 1.68 - 0.72^2[/tex]
[tex]Var(x) = 1.1616[/tex]
Solving (c): The standard deviation.
This is calculated as:
[tex]\sigma = \sqrt{Var(x)}[/tex]
[tex]\sigma = \sqrt{1.1616}[/tex]
[tex]\sigma = 1.078[/tex]
Solving (2):
[tex]\begin{array}{ccccccc}{x} & {10} & {11} & {12} & {13} & {14}& { } \ \\ {P(x)} & {0.1} & {0.25} & {0.3} & {0.25} & {0.1} & { } \ \end{array}[/tex]
(a): Mean
This is calculated as:
[tex]E(x) = \sum x * P(x)[/tex]
So, we have:
[tex]E(x) = 10 * 0.10 + 11 * 0.25 + 12 * 0.3 + 13 * 0.25 + 14 * 0.1[/tex]
[tex]E(x) = 12[/tex]
Solving (b): The variance
This is calculated as:
[tex]Var(x) = E(x^2) - (E(x))^2[/tex]
Where:
[tex]E(x) = 12[/tex]
and [tex]E(x^2) = \sum x^2 * P(x)[/tex]
So, we have:
[tex]E(x^2) = 10^2 * 0.10 + 11^2 * 0.25 + 12^2 * 0.3 + 13^2 * 0.25 + 14^2 * 0.1[/tex]
[tex]E(x^2) = 145.3[/tex]
So, we have:
[tex]Var(x) = E(x^2) - (E(x))^2[/tex]
[tex]Var(x) = 145.3 - 12^2[/tex]
[tex]Var(x) = 1.3[/tex]
Solving (c): The standard deviation.
This is calculated as:
[tex]\sigma = \sqrt{Var(x)}[/tex]
[tex]\sigma = \sqrt{1.3}[/tex]
[tex]\sigma = 1.14[/tex]
A girl has 9 skirts, 8 blouses, and 7 pairs of shoes. How many different skirt-blouse-shoe outfits can
she wear? (Assume that each item matches all the others, so she is willing to wear any combination.)
Answer:
She could wear 7 different outfits
The mean is 47.1 and the standard deviation is 9.5 for a population. Using the Central Limit Theorem, what is the standard deviation of the distribution of sample means for samples of size 60
Answer:
The standard deviation of the distribution of sample means for samples of size 60 is of 1.2264.
Step-by-step explanation:
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.
Standard deviation is 9.5 for a population.
This means that [tex]\sigma = 9.5[/tex]
Sample of 60:
This means that [tex]n = 60[/tex]
What is the standard deviation of the distribution of sample means for samples of size 60?
[tex]s = \frac{\sigma}{\sqrt{n}} = \frac{9.5}{\sqrt{60}} = 1.2264[/tex]
The standard deviation of the distribution of sample means for samples of size 60 is of 1.2264.
1,547,489 which digit is in the thousandsths place
Answer:
7
Step-by-step explanation:
Answer:
7
Step-by-step explanation:
Starting from right to left...
9 is in the ones place
8 is in the tenths place
4 is in the hundreds place
7 is in the thousands place.
I hope this helps!
What balance will be in an account that has an initial deposit of $4600 with an APR of
1.8%? The money is compounded quarterly for 30 years.
How much interest has been earned for the entire time period?
Answer:
100$or 20.4 that is the answer
Find the value of a for which there is no term independent of x in the ezlxpansion of
[tex](1 + ax {}^{2} )( \frac{2}{x} - 3x) {}^{6} [/tex]
"no terms independent of x" basically means there is no constant term, or the coefficient of x ⁰ is zero.
Recall the binomial theorem:
[tex]\displaystyle (a+b)^n=\sum_{k=0}^n\binom nk a^{n-k}b^k[/tex]
So we have
[tex]\displaystyle \left(1+ax^2\right)\left(\frac2x-3x\right)^6 = \left(1+ax^2\right) \sum_{k=0}^6 \binom 6k \left(\frac2x\right)^{6-k}(-3x)^k[/tex]
[tex]\displaystyle \left(1+ax^2\right)\left(\frac2x-3x\right)^6 = \left(1+ax^2\right) \sum_{k=0}^6 2^{6-k}(-3)^k\binom 6k x^{2k-6}[/tex]
[tex]\displaystyle \left(1+ax^2\right)\left(\frac2x-3x\right)^6 = \sum_{k=0}^6 2^{6-k}(-3)^k\binom 6k x^{2k-6}+a\sum_{k=0}^6 2^{6-k}(-3)^k\binom 6k x^{2k-4}[/tex]
The first sum contributes a x ⁰ term for 2k - 6 = 0, or k = 3, while the second sum contributes a x ⁰ term for 2k - 4 = 0, or k = 2. The coefficient of the sum of these terms must be zero:
[tex]2^{6-3}(-3)^3\dbinom 63 + a\times2^{6-2}(-3)^2\dbinom 62 = 0[/tex]
which reduces to
2160a - 4320 = 0
2160a = 4320
a = 2
Need answers please offering 30 points
Answer:
yefeihuerijohiftv3ugrhoerfujfy
Step-by-step explanation:
Calculate the exact slope m (rather than a decimal approximation) of the straight line through the given pair of points, if defined. Try to do the problem without writing anything down except the answer. (If an answer is undefined, enter UNDEFINED.)
(6, 7) and (7, 1)
Answer:
m = -6
Step-by-step explanation:
The slope of a line is calculated as the change in y divided by the change in x.
Teachers use the phrase "rise over run". In this case the rise is negative as the line moves from a higher y value to a lower y value as x increases.
(y-final - y-initial)/(x-final - x-initial)
You are given two points on the line and just plug them in.
(1-7)/(7-6) = -6/1 = -6
Jack is a discus thrower and hopes to make it to the Olympics some day. He has researched the distance (in meters) of each men's gold medal discus throw from the Olympics from 1920 to 1964. Below is the equation of the line of best fit Jack found.
y = 0.34x + 44.63
When calculating his line of best fit, Jack let x represent the number of years since 1920 (so x=0 represents 1920 and x=4 represents 1924).
Using the line of best fit, estimate what the distance of the gold medal winning discus throw was in 1980.
71.83 meters
65.03 meters
717.83 meters
44.63 meters
Answer:
65.03 meters
Step-by-step explanation:
The line of best fit, for the distance of the winning throw, in x years after 1980 is:
[tex]y = 0.34x + 44.63[/tex]
Using the line of best fit, estimate what the distance of the gold medal winning discus throw was in 1980.
1980 - 1920 = 60, so this is y(60).
[tex]y(60) = 0.34(60) + 44.63 = 65.03[/tex]
So the answer is 65.03 meters.
a rice cooker was sold for $60 after a discount of 60% waht was the usual price of the rice cooker plz simple for class 5 pleeease
Answer:
$150
Step-by-step explanation:
discount=60%
let the price=x
(100-60)% of x=$60
40% of x=60
x=60×(100/40)=150
Economists have found that the amount of corruption in a country's government is correlated to the gross domestic product (GDP) per capita of that country. This can be modeled by y=530x−9240 where x is the corruption score and y is GDP per capita in dollars. Corruption scores range from 0 to 100 with 0 being highly corrupt and 100 being least corrupt. what is the slope of the line represent?
A. the GDP per capita of the country with the lowest corruption score
B. the corruption score needed for a GDP per capita of zero
C. the average GDP per capita for every point in the corruption score
D. the increase in GDP per capita for every increase of one in corruption score
Step-by-step explanation:
pandemic times: Potential ... - CAF
have shown evidence that the effect of corruption on real GDP per capita is more pronounced in countries with low levels of8
The function f(x) is shown on the provided graph. Graph the result of the following transformation on f(x). f(x) +6
Answer:
Graph the same exact curve, but move every y value up 6.
Step-by-step explanation:
A transformation to the y-values is outside of the argument of the function. i.e., outside of the parentheses.
One 8.3 ounce can of Red Bull contains energy in two forms: 27 grams of sugar and 80 milligrams of caffeine. One 23.5 ounce can of Jolt Cola contains 94 grams of sugar and 280 milligrams of caffeine. Determine the number of cans of each drink that when combined will contain 457 grams sugar and 1360 milligrams caffeine. We need cans of Red Bull, and cans of Jolt.
Of 240 stamps that Harry and his sister collected, Harry collected 3 times as many as his sister. How many did each collected.
Answer:
Harry collected 180 stamps
Harry's sister collected 60 stamps
Step-by-step explanation:
Let X be the number of stamps that Harry's sister colleted.
The number of stamps Harry colleted is 3 time as many as his sister's
⇒ 3*X + X = 240
⇒ X = 60
⇒ 240 - 60= 180
Answer:
180 for harry and 60 for his sister
Step-by-step explanation:
Sketch a graph of f (x) = −1
Answer:
Step-by-step explanation:
f(x) = -1 is actually the same as y = -1. Find y = -1 on the y axis and then draw a horizontal line through this point. The resulting graph is that called for here.
If g(x) = x2 – 4, find g(5).
6
О
14
21
O
29
[tex]\boxed{ \sf{Answer}} [/tex]
[tex]\sf \: g(x) = {x}^{2} - 4 \\ \\ \sf \: x = 5 \\ \\ \sf \: g(5) = {5}^{2} - 4 \\ \sf \: g(5) = 25 - 4 \\ \sf \: g(5) =\underline 2\underline1[/tex]
Answer ↦21 [Option C]
[tex]\tt \: g(x) = {x}^{2} - 4[/tex]
Substitute the value of x as 5 (given) in the above equation. The equation changes too..
[tex]\tt \: g(5) = {5}^{2} - 4[/tex]
Now you can easily solve the equation.
[tex]\tt \: g(5) = {5}^{2} - 4 \\\tt g(5) =( 5 \times 5) - 4 \\ \tt \: g(5) = 25 - 4 \\ \tt \: g(5) = 21[/tex]
Answer - [tex]\boxed{\sf{21}}[/tex]
Find the time required for an investment to double in value if invested in an account paying 3% compounded quarterly.
Answer: [tex]6.12\ \text{years}[/tex]
Step-by-step explanation:
Given
Rate of interest is [tex]r=3\%[/tex] compounded quarterly
So, annually it is [tex]r=12\%[/tex]
Suppose [tex]P[/tex] is the Principal and A is the amount after certain time period.
Amount in Compound interest is given by
[tex]\Rightarrow A=P[1+r\%]^t[/tex]
for given conditions
[tex]\Rightarrow 2P=P[1+0.12]^t\\\Rightarrow 2=(1.12)^t\\\\\Rightarrow t=\dfrac{\ln (2)}{\ln (1.12)}\\\\\Rightarrow t=6.116\approx 6.12\ \text{years}[/tex]
It take [tex]6.12\ \text{years}[/tex] to double the invested amount.
Suppose 180 randomly selected people are surveyed to determine whether or not they plan on voting to reelect the current president. Of the 180 surveyed, 36 reported they will not vote to reelect the current president. Identify the values needed to calculate a confidence interval for the proportion that will not vote to reelect the current president at the 99% confidence level. Then find the confidence interval.
Answer:
(0.123 ; 0.277)
Step-by-step explanation:
Given :
Sample size, n = 180
x = 36
Proportion, p = x / n = 36/180 = 0.2
Confidence interval for sample proportion :
Confidence interval :
p ± Zcritical * √p(1 - p) / n
Zcritical at 99% = 2.576
0.2 ± 2.576 * √0.2(1 - 0.2) / 180
0.2 ± 2.576 * 0.0298142
0.2 ± 0.0768013792
(0.123 ; 0.277)
For f(x) = 4x2 + 13x + 10, find all values of a for which f(a) = 7.
The solution set is ???
i keep getting -2, -1/5 ... but it’s telling me it’s wrong. help!.
(Type an integer or a simplified fraction. Use a comma to separate answers as needed.)
Answer:
0.84
Step-by-step explanation:
4x2+13a+10=7
13a=7-10-8
13a=-11
a=-11:13
a=0.84