Answer:
[tex] \bar X = \frac{\sum_{i=1}^{42} X_i}{n}[/tex]
And for this case the sample mean is
[tex]\bar X = 127.1[/tex]
And this value is calculated from a sample so then can't represent a population parameter. Then the value 127.1 represent a statistic called the sample mean unbiased for the true population mean since [tex] E(\bar X) =\mu[/tex], and the best option would be:
D) The given value is a statistic for the year because the data collected represent a sample.
Step-by-step explanation:
For this case we know that a homeowner take a random sample of 42 voltage values ina year and he calculate the sample mean with this formula:
[tex] \bar X = \frac{\sum_{i=1}^{42} X_i}{n}[/tex]
And for this case the sample mean is
[tex]\bar X = 127.1[/tex]
And this value is calculated from a sample so then can't represent a population parameter. Then the value 127.1 represent a statistic called the sample mean unbiased for the true population mean since [tex] E(\bar X) =\mu[/tex], and the best option would be:
D) The given value is a statistic for the year because the data collected represent a sample.
Choose the following which is COMPLETELY correct:
Answer:
D
Step-by-step explanation:
Mean = (4+4+5+8+9) / 5
30 / 5
6
Median = put them in order and the one in the middle is the median.
4, 4, 5, 8, 9
Mode = the most common
4, 4, 5, 8, 9
Directions and Analysis
Task 1: Completing the Square
Look at the quadratic equation below.
2x^2-12x-16=0
This is not an equation that could be easily solved by factoring. Instead, you are going to use the method of completing the square to solve this equation. Follow each step in this task to complete the square and solve the equation.
a. To complete the square, the coefficient of the x2 term must be 1. Divide both sides of the equation by a value and rewrite the equation to meet this criteria.
Type your response here:
b. Rewrite the resulting equation so the constant term is on the right side of the equation and the variable terms are on the left.
Type your response here:
c. Identify the coefficient of the x term in the previous equation. Then divide it by half and square the result. What is the result?
Type your response here:
d. Add the value you identified in part c to both sides of the equation from part b and simplify the right side. Remember that when solving equations, whatever is done to one side of the equation must also be done to the other side the equation: that is why you must add the value to both sides.
Type your response here:
e. Notice that the left side of the equation now represents a perfect square quadratic expression. Use this fact to rewrite the left side of the previous equation as the square of a linear term and create a new equation.
Type your response here:
f. You have now completed the square. Starting with the result from part e, solve the equation for x. Show your work.
Type your response here:
g. Now that you know how to complete the square to solve a quadratic equation, solve the equation 3x^2 – 3x − 6 = 0. Show your work.
Type your response here:
Answer:
a. [tex]x^2-6x-8=0[/tex]
b. [tex]x^2-6x=8[/tex]
c.
[tex]\frac{1}{2}[/tex] (Coefficient of x) = [tex]\frac{-6}{2}=-3[/tex]
Also, [tex](-3)^2=9[/tex]
d. [tex]x^2-6x+9=17[/tex]
e. [tex](x-3)^2=17[/tex]
f, g. [tex]x=3\pm \sqrt{17}[/tex]
Step-by-step explanation:
Given: [tex]2x^2-12x-16=0[/tex]
To solve: the given equation
Solution:
a.
[tex]2x^2-12x-16=0[/tex]
Coefficient of [tex]x^2=2[/tex]
Divide both sides by 2
[tex]x^2-6x-8=0[/tex]
b.
[tex]x^2-6x=8[/tex]
c.
Coefficient of x = -6
[tex]\frac{1}{2}[/tex] (Coefficient of x) = [tex]\frac{-6}{2}=-3[/tex]
Also, [tex](-3)^2=9[/tex]
d.
Add 9 to both sides of the equation: [tex]x^2-6x=8[/tex]
[tex]x^2-6x+9=8+9\\x^2-6x+9=17[/tex]
e.
[tex]x^2-6x+9=17\\x^2-2(3)x+3^2=17\\(x-3)^2=17\,\,\left \{ \because (a-b)^2=a^2+b^2-2ab \right \}[/tex]
f.
[tex](x-3)^2=17\\x-3=\pm \sqrt{17}\\x=3\pm \sqrt{17}[/tex]
g.
[tex]x=3\pm \sqrt{17}[/tex]
The following stem-and-leaf plots compare the ages of 30 actors and 30 actresses at the time they won the Oscar award for Best Actor or Actress. Actors Stems Actresses 2 146667 98753221 3 00113344455778 88776543322100 4 11129 6651 5 210 6 011 6 7 4 8 0 (a) What is the age of the youngest actor to win an Oscar? years (b) What is the age difference between the oldest and the youngest actress to win an Oscar? years (c) What is the oldest age shared by two actors to win an Oscar?
The image of the stem-and-leaf plots is in the attachment.
Answer: (a) 31 years; (b) 59 years; (c) 56 years
Step-by-step explanation: Steam and leaf is a table that shows the digits of the data value split into a "stem", which represents the first digit, and a "leaf", which is the last digit.
For example, the first row of the table in the attachment, indicate a "stem" 2 and the first number of a "leaf" is 1, so the actress has 21 years.
(a) According to the table, the youngest actor to win an Oscar has a "stem" 3 and the first "leaf" from the right is 1, so the actor has 31 years.
(b) The oldest actress is 80 and the youngest is 21, so difference is:
80 - 21 = 59
The difference is 59 years.
(c) The oldest age shared by 2 actors is 56 years.
A fraction with a zero in the numerator equals
Answer:Any legal fraction (denominator not equal to zero) with a numerator equal to zero has an overall value of zero. all have a fraction value of zero because the numerators are equal to zero.
Mathematics: The graph below have the same shape. What is the equation of the blue graph?
Answer:
Since the blue graph is the red graph translated 3 units to the left the answer is D.
Lydia is going to invest $210 and leave it in an account for 17 years. Assuming the interest is compounded daily, what interest rate, to the nearest hundredth of a percent, would be required in order for Lydia to end up with $330?
Answer:
To the nearest hundredth of a percentage= 0.03
Step-by-step explanation:
Formula for compound interest
A= p(1+r/n)^nt
A= $330
P= $210
n = 356
t= 17
r = ?
330 = 210(1+r/356)^(356*17)
330 = 210(1+r/356)^(6052)
330/210 = (1+r/356)^6052
(6052√(330/210) - 1 )356 = r
(1.000074686-1)356= r
0.02658 = r
To the nearest hundredth of a percentage= 0.03
Answer:
2.66
Step-by-step explanation:
According to the February 2008 Federal Trade Commission report on consumer fraud and identity theft, 23% of all complaints in 2007 were for identity theft. In that year, Alaska had 321 complaints of identity theft out of 1,432 consumer complaints (Consumer fraud and, 2008). (7.1.2)
State the random variable, population parameter, and hypotheses.
Answer:
Random variable: for this case represent the number of complaints in 2007
Population parameter: represent the real proportion of complaints in 2007 p
Hypothesis to verify
We want to check if the true proportion of complaints in 2007 is equal to 0.23, the system of hypothesis are.:
Null hypothesis:[tex]p=0.23[/tex]
Alternative hypothesis:[tex]p \neq 0.23[/tex]
Step-by-step explanation:
Information provided
n=1432 represent the random sample taken
X=321 represent the number of complaints
[tex]\hat p=\frac{321}{1432}=0.224[/tex] estimated proportion of complaints in 2007
[tex]p_o=0.23[/tex] is the value to verify
z would represent the statistic
Random variable: for this case represent the number of complaints in 2007
Population parameter: represent the real proportion of complaints in 2007 p
Hypothesis to verify
We want to check if the true proportion of complaints in 2007 is equal to 0.23, the system of hypothesis are.:
Null hypothesis:[tex]p=0.23[/tex]
Alternative hypothesis:[tex]p \neq 0.23[/tex]
Find w and y, will give brainliest for the correct answer
Answer: w=12, y=6√3
Step-by-step explanation:
Looking at the figure, we can split the triangle into 2 separate triangles. One on the left and one on the left. The triangle on the right is a 30-60-90 triangle. For this triangle, the hypotenuse is 2x in length. This is directly opposite of the right angle. The leg opposite to 30° is x in length. The leg opposite 60° is x√3 in length. Once you know the length of one side, you can plug in x to find the length of the other legs.
In this case, w and y are located on the same 30-60-90 triangle. Normally we would focus on that triangle to find our values, but in this instance, we don't have any values. We have to use the left triangle to find the leg that both triangles share.
The left triangle is a 45-45-90 triangle. For this triangle, the legs opposite of 45° is x in length. The hypotenuse is x√2. Since we know the hypotenuse, we can use it to find x.
x√2=8
x=8/√2
x=5.7 or 6 [Let's use 6 so that it is easier to work with a whole number]
Now that we know x, we can find w and y. Going back to the right triangle, we know the hypotenuse is 2x. We plug in 6 to find the length.
w=2x
w=2(6)
w=12
We know the leg opposite of 60° is x√3. We can plug in x.
y=6√3
Increase £130 by 15%
Answer:
£149.5
Step-by-step explanation:
[tex]100 + 15 = 115\\115/100 = 1.15\\130 * 1.15 = 149.5[/tex]
Find the number of ways of arranging the numbers 1,2,3,4,5,6,7, if no two even numbers can be adjacent, and no two odd numbers can be adjacent.
Answer:
24 ways
Step-by-step explanation:
1) In Combinatorics when we arrange a number and the order matter, we call it arrange the possibilities. For this exercise let's not use formulas but reasoning.
2) For this case we need a two figure number. Since we have seven numbers.
Since there is no repetition, all the possibilities are:
[tex]7*6=42[/tex]
3) But there is a restriction it's forbidden adjacent even and odd numbers: These numbers we don't want them:
13 15 17
24 26
31 35 37
42 46
51 53 57
62 66
71 73 75
18 non desirable results
The total arrangements minus the not possible combinations, will match the possible results:
[tex]42-18=24[/tex]
3) Just for checking, we have here the allowed combinations:
12 14 16
21 23 25 27
32 34 36
41 43 45 47
52 54 56
61 63 65 67
72 74 76
A total of 24 possible ways.
If 3^2+1 =3^x+5. What is the value of x?
Answer:
[tex]x=1.464974[/tex]
Step-by-step explanation:
[tex]3^2+1 =3^x+5[/tex]
[tex]9+1 =3^x+5[/tex]
[tex]10 =3^x+5[/tex]
[tex]10-5 =3^x[/tex]
[tex]5=3^x[/tex]
[tex]log(3x)=log(5)[/tex]
[tex]x \times (log(3))=log(5)[/tex]
[tex]x=\frac{log(5)}{log(3)}[/tex]
[tex]x=1.464974[/tex]
Answer: 1.46497352 or 1.5
Step-by-step explanation:
Complete 3^2 to get 9, then add 1 to get 10
Then subtract 5 from both sides to get [tex]5=3^x[/tex]
Youre gonna have to apply a log rule here to get:
[tex]log_{3}5=x[/tex]
You get 1.46497352 or approximately 1.5
Area of composed figure. Parallelogram, square and a rectangle
Answer:
126 in²
Dude just trust me
Which linear function has initial value 4?
a. y = 3x - 4
b. y = - 3x + 4
c. y = 4x - 3
d. y = 4x + 3
Answer:
y = -3x+4
Step-by-step explanation:
An initial value of 4 would be the y intercept
The only function with a y intercept of 4
(y = mx+b where b is the y intercept)
is y = -3x+4
Tamar rides her bike 960 feet in 2 minutes. What is her rate of speed?
Answer:
Rate of speed = 480 feet per minutes
Step-by-step explanation:
Given:
Distance covered by bike = 960 feet
Time taken to covered distance = 2 minutes
Find:
Rate of speed = ?
Computation:
⇒ Speed = Distance / Time
⇒ Rate of speed = Distance covered by bike / Time taken to covered distance
⇒ Rate of speed = 960 / 2
⇒ Rate of speed = 480 feet per minutes
Estimate the quotient 241 ÷ 5. A. 40 B. 250 C. 50 D. 60
Answer:
The quotient of 241 ÷ 5 is 48.
Step-by-step explanation:
Division is splitting into equal parts or groups.
The quotient is the answer after we divide one number by another.
To find the quotient 241 ÷ 5 you must:
Write the problem in long division format
[tex]5\overline{|\smallspace241}[/tex]
Divide 24 by 5 to get 4
Multiply the quotient digit 4 by the divisor 5
Subtract 20 from 24
Bring down the next number of the dividend
Divide 41 by 5 to get 8
Multiply the quotient digit 8 by the divisor 5
Subtract 40 from 41
[tex]\mathrm{The\:solution\:for\:Long\:Division\:of}\:\frac{241}{5}\:\mathrm{is}\:48\:\mathrm{with\:remainder\:of}\:1\\\\48\quad \mathrm{Remainder}\quad \:1[/tex]
What is the slope of a line that is perpendicular to the line y = x + 5?
Answer:
-1.
Step-by-step explanation:
The standard form of a line can be written y = mx + b where m is the slope.
y = x + 5 can be written as y = 1x + 5 which shows that the slope is 1.
If the slope of a line is m then the slope of a line perpendicular to it is -1/m.
So the required slope is -1/1 = -1.
Answer:
-1
Step-by-step explanation:
the line is exactly opposite like a mirror image when it is perpendicular,
so the gradient of the first line is 1 (because there is no number beside x, the gradient would be 1), that means the opposite of 1 would be -1.
The answer is -1
In a poll sponsored by Nick's Corn Farm, 1300 randomly selected adults were asked to select their favorite vegetable. The favorite choice from the poll was corn on the cob, which was selected by 40% of the respondents. What is wrong statistically
Answer:
The fact that two variables are correlated does not necessarily mean that one causes the other.
Step-by-step explanation:
We must start from the fact that there are two variables in the exercise and according to what they tell us they are related to each other, but statistically speaking the fact that two variables are correlated does not necessarily mean that one causes the other, therefore this would be statistically wrong.
I NEED HELP PLEASE HELP ME PLEASEEE
Answer:
The answer is 2.5 hours
Step-by-step explanation:
A fast food hamburger restaurant uses 3,500 lbs. of hamburger each week. The manager of the restaurant wants to ensure that the meat is always fresh i.e. the meat should be no more than two days old on average when used. How much hamburger should be kept in the refrigerator as inventory
Answer:
The peak inventory will be 2 sales days of hamburguers, which is equivalent to 7,000 lbs. As they are consumed in 2 days, the average inventory is 3,500 lbs.
Step-by-step explanation:
If the meat should be no more than two days old on average when used, the stock of hamburguer in the refrigerator has to be at most the equivalent to 2 day of sales.
The "2 days old" represents the inventory turnover.
If we use all the hamburguers in the refrigerator and refill inmediatly, the average inventory is:
[tex]\bar I=\dfrac{\text{Beginning inventory}+\text{Ending inventory}}{2}\\\\\\\bar I=\dfrac{2*3,500+0}{2}=3,500[/tex]
The peak inventory will be 2 sales days of hamburguers, which is equivalent to 7,000 lbs. As they are consumed in 2 days, the average inventory is 3,500 lbs.
The cost of 4kg of Apple and 6kg of orange is Rs620.If the cost of orange is the same as the cost of 5 kg Apple find the cost of per kg of Apple and orange?
Answer:
The apple cost RS 18.24 per kg, while
the orange cost RS 91.18 per kg.
Step-by-step explanation:
Let the cost of 1kg if apple and orange be RS A and RS O respectively.
From the first line:
4A +6O= 620
2A +3O= 310 -----(1) (÷2 throughout)
From the information given in second line:
O= 5A -----(2)
subst. (2) into (1):
2A +3(5A)= 310
2A +15A= 310 (expand)
17A= 310 (simplify)
A= 310 ÷17 (÷17 on both sides)
A= 18.235 (5 s.f.)
A= 18.24 (2 d.p.)
Subst. into (2):
O= 5(18.235)
O= 91.18 (2 d.p.)
What is the next pattern ?
If the center of a circle is at
(5,-3) and its radius is 4, complete
its equation:
Answer:
Step-by-step explanation:
[tex](x-5)^2+(y-(-3))^2=16[/tex]
Alex needs
80
cm
80 cm80, start text, space, c, m, end text of thread for a sewing project. The thread is on a spool with a circumference of
10
cm
10 cm10, start text, space, c, m, end text.
How many times must Alex unwind the spool to get the length of thread he needs?
Answer:
8 full turns
Step-by-step explanation:
80 cm is 8 times 10 cm, so is 8 times around the spool.
Alex must unwind 8 full turns of thread from the spool.
__
He must unwind it once.
Answer:
8 in total turns
Step-by-step explanation:
Construct the indicated confidence interval for the difference between the two population means. Assume that the two samples are independent simple random samples selected from normally distributed populations. Do not assume that the population standard deviations are equal.
A paint manufacturer wished to compare the drying times of two different types of paint. Independent simple random samples of 11 cans of type A and 9 cans of type B were selected and applied to similar surfaces. The drying times, in hours, were recorded. The summary statistics are as follows.
Type A
x-bar1 = 75.7 hrs.
s1 = 4.5 hrs.
n1 = 11
Type B
x-bar2 = 64.3 hrs.
s2 = 5.1 hrs.
n2 = 9
Construct a 98% confidence interval for the difference for the mean drying time between paint A and paint B.
A. 6.08 hrs < μ1 - μ2 < 16.72 hrs
B. 5.85 hrs < μ1 - μ2 < 16.95 hrs
C. 5.78 hrs < μ1 - μ2 < 17.02 hrs
D. 5.92 hrs < μ1 - μ2 < 16.88 hrs
Answer:
Step-by-step explanation:
The formula for determining the confidence interval for the difference of two population means is expressed as
Confidence interval = (x1 - x2) ± z√(s²/n1 + s2²/n2)
Where
x1 = sample mean of type A paint
x2 = sample mean of type B paint
s1 = sample standard deviation type A paint
s2 = sample standard for type B paint
n1 = number of samples of type A paint
n2 = number of samples of type B paint
From the information given,
x1 = 75.7
s1 = 4.5
n1 = 11
x2 = 64.3
s2 = 5.1
n2 = 9
x1 - x2 = 75.7 - 64.3 = 11.4
√(s1²/n1 + s2²/n2) = √(4.5²/11 + 5.1²/9) = √4.709
Degree of freedom = (n1 - 1) + (n2 - 1)
df = (11 - 1) + (9 - 1) = 18
For the 98% confidence interval, the z score from the t distribution table is 2.552
Margin of error = 2.552√4.709 = 5.55
The upper boundary for the confidence interval is
11.4 + 5.55 = 16.95 hours
The lower boundary for the confidence interval is
11.4 - 5.55 = 5.85 hours
The correct option is
B. 5.85 hrs < μ1 - μ2 < 16.95 hrs
An amusement park is installing a new roller coaster. the park intends to charge $5 per adult and $3 per child for each ride. It hopes to earn back more than the $750,000 cost of construction in four years. with the best of weather, the park can provide 100000 adult rides and 75,000 child rides in one season.
Answer:
Cost = 750,000
Income per year = 5 x 100,000 + 75,000 x 3 = 725,000
Income for 4 years = 4 x 725,000 = 2,900,000
Profit = 2,900,000 - 750,000 = 2,150,000
Step-by-step explanation:
Which of the following gives all of the sets that contain sqare root 9
1 the set of all irrational numbers
2.the set of all natural numbers, the set of all whole numbers, and the set of all integers
3. the set of all integers, the set of all rational numbers, and the set of all real numbers
4. the set of all natural numbers, the set of all whole numbers, the set of all integers, the set of all rational numbers, and the set of all real numbers
Answer:
4. the set of all natural numbers, the set of all whole numbers, the set of all integers, the set of all rational numbers, and the set of all real numbers
Step-by-step explanation:
√9 = 3
3 is every kind of number except irrational. It belongs to the sets of ...
natural numberswhole numbersintegersrational numbersreal numbersIn a particular region, for families with a combined income of $75,000 or more, 15% of these families have no children, 35% of the families have one child, 45% have two children, and 5% have three children. Use this information to construct the probability distribution for X, where x represents the number of children per family for this income group. Arrange x in increasing order and write the probabilities P(x) as decimals
Answer:
The probability distribution for x:"number of children per family for this income group" is:
[tex]\text{P(x=0)}=0.15\\\\\text{P(x=1)}=0.35\\\\\text{P(x=2)}=0.45\\\\\text{P(x=3)}=0.05\\\\[/tex]
Step-by-step explanation:
With the information given we have the relative frequencies of each category.
We know:
[tex]\text{P(x=0)}=0.15\\\\\text{P(x=1)}=0.35\\\\\text{P(x=2)}=0.45\\\\\text{P(x=3)}=0.05\\\\[/tex]
WILL GIVE BRAINLIEST! HURRY
Answer:
-1/2 =x
Step-by-step explanation:
4x - 6 = 10x -3
Subtract 4x from each side
4x-4x - 6 = 10x-4x -3
-6 = 6x-3
Add 3 to each side
-6+3 = 6x
-3 = 6x
Divide each side by 6
-3/6 = 6x/6
-1/2 =x
[tex]answer \\ - \frac{1}{2} \\ solution \\ 4x - 6 = 10x - 3 \\ or \: 4x - 10x = - 3 + 6 \\ or \: - 6x = 3 \\ or \: x = \frac{3}{ - 6} \\ x = - \frac{1}{2} \\ hope \: it \: helps[/tex]
What is the quotient 5^-6 over 5^3
Answer:
1/ 5^9
Step-by-step explanation:
5^-6/5^3
5^(-6-3)
5^-9
Final Answer - 1/5^9
Classify the following triangle check all that apply. 98,41,41
Answer:
B. Isosceles triangle
Answer: obtuse and isosceles <3
Step-by-step explanation: