Answer: Another way to describe the area of a triangle is by saying it is half of the product of its base and height
Step-by-step explanation:
A certain test preparation course is designed to help students improve their scores on the GRE exam. A mock exam is given at the beginning and end of the course to determine the effectiveness of the course. The following measurements are the net change in 5 students' scores on the exam after completing the course: 6,14,12,23,0 Using these data, construct a 95% confidence interval for the average net change in a student's score after completing the course. Assume the population is approximately normal. Step 2 of 4 : Calculate the sample standard deviation for the given sample data. Round your answer to one decimal place.
Answer:
(0.25 ; 21.75)
8.7 (1 decimal place)
Step-by-step explanation:
Net change in scores : X = 6,14,12,23,0
Sample mean, xbar = (6 + 14 + 12 + 23 + 0) /5 = 55 /5 = 11
Sample standard deviation, s = 8.66 ( from calculator)
Sample standard deviation = 8.7( 1 decimal place)
Sample size, n = 5
The 95% confidence interval; we use t, because n is small
Tcritical at 95%, df = 4 - 1 = 3 ; Tcritical = 2.776
Xbar ± standard Error
Standard Error = Tcritical * s/√n
Standard Error = 2.776 * 8.66/√5
Standard Error = 10.751086 = 10.75
Lower boundary = (11 - 10.75) = 0.25
Upper boundary = (11 + 10.75) = 21.75
(0.25 ; 21.75)
The
The value -1 is a solution for x2 - 6x+ 5 = 0.
True or false
Answer:
false
Step-by-step explanation:
If -1 us a solution then putting -1 in place of x will be 0[tex] \rm \dashrightarrow \: {x}^{2} - 6x + 5 = 0 \\ \rm \dashrightarrow \: {( - 1)}^{2} - 6( - 1) + 5 = 0 \\ \rm \dashrightarrow \: 1 + 6 + 5 = 0 \\ \rm \dashrightarrow \: 7 + 5 = 0 \\ \rm \dashrightarrow \: 12 \cancel{ = }0[/tex]
Which of the following is a solution to the equation sin (x) + 2 = 1
Answer:
-1
Step-by-step explanation:
Anybody know the answer to this it would be very helpful
Answer:
The cost for 4 snacks is 18 dollars.
Cost for x snacks: 4.5x
Step-by-step explanation:
4 x 4.5 = 18
Answers:
Cost for 4 snacks = 70 dollarsCost for x snacks = 4.50x+52 dollarsThe algebraic expression shown above is the same as writing 52+4.50x
You may not need to type in "dollars" or a dollar sign, as your teacher may just want the numbers and algebraic symbols.
=====================================================
Explanation:
There are four people going to the movies, and each ticket costs $13 a piece, so that means the total so far is 4*13 = 52 dollars.
If we want to include snacks, then it costs $4.50 per snack. Buying 4 packages will cost an additional 4.50*4 = 18 dollars. In total, if Kiran wants to buy four snacks, then he'll need 52+18 = 70 dollars.
---------------------
Instead of computing 4.50*4 to get 18, we can leave the "4.50*4" like it is. Adding it onto the 52 found earlier leads to the expression 52+4.50*4
Now imagine that instead of "4", we just had a generic placeholder x take over. The x is standing in for any positive real number, or it could stand in for 0 if Kiran decides to not buy any snacks at all.
If we replace that "4" with x, then the expression
52+4.50*4
is the same as
52+4.50*x
Often times, you'll see the multiplication symbol omitted and the expression could look like 52+4.50x
Because we can add two numbers in any order, that expression above is the same as 4.50x+52
-------------------
Extra info (optional section):
The useful thing about something like 4.50x+52 is that we can graph y = 4.50x+52 and/or set up a table to be able to quickly determine how much money it will cost for buying any amount of snacks.
For example, let's say he wants to buy 10 snacks. That means we replace x with 10 and evaluate like so
4.50x+52 = 4.50*10+52 = 45+52 = 97
Buying 10 snacks, on top of the 4 movie tickets, cost $97 in total.
A true-false examination was constructed with the answers running in the following sequence: T F F T F T F T T F T F F T F T F T T F Does this sequence indicate a departure from randomness in the arrangement of T and F answers?
Answer:
yes
Step-by-step explanation:
lets use a significance level of = 0.1
Determine if the sequence indicates randomness
First step :
H0 : pattern is random
H1 : pattern not random
n1 ( number of true answers ) = 10
n2 ( number of false answers ) = 10
also number of runs for T = 5
number of runs for F = 5
Total number of runs = 5+ 5 = 10
Given that critical value at 0.05 = 23
we will reject the null hypothesis ( i.e the sequence departs from randomness )
NEED HELP FAST CLICK TO SEE PLS
Answer:
Last Option
Step-by-step explanation:
Last one because the dot on top of the 4 is filled in and that means it can also equal 4. The rest of the line is going to the right of the 4 so x will be more than 4. The little line below the more than sign means it can also equal 4. Hope this helped :)
Answer:
Option D, x ≥ 4
Step-by-step explanation:
Rule 1: Closed circle: the inequality sign with a line at the bottom, its called greater than or equal to (≥), and less than or equal to (≤), that means that the number 4 is included in the data set.
Rule 2: Since the line is going to the right of 4, there are values greater than 4 in the data set which means x (any value) has to be greater than 4.
So bringing both rules together the equation would be: x ≥ 4
Hope this helps!
A survey was initiated and intended to capture the prevalence of specific learning disorder (SLD) among school-aged children with autism spectrum disorder (ASD). Out of a sample of 1,483 participants, a total of 241 were found to have SLD. Calculate 95% confidence interval for the proportion of participants who have SLD among the children with ASD.
Answer:
The 95% confidence interval for the proportion of participants who have SLD among the children with ASD is (0.1437, 0.1813).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
Out of a sample of 1,483 participants, a total of 241 were found to have SLD.
This means that [tex]n = 1483, \pi = \frac{241}{1483} = 0.1625[/tex]
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.1625 - 1.96\sqrt{\frac{0.1625*0.8375}{1483}} = 0.1437[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.1625 + 1.96\sqrt{\frac{0.1625*0.8375}{1483}} = 0.1813[/tex]
The 95% confidence interval for the proportion of participants who have SLD among the children with ASD is (0.1437, 0.1813).
Match each equation on the left with the number and type of its solutions on the right.
Answer:
Step-by-step explanation:
1). Given equation is,
2x² - 3x = 6
2x² - 3x - 6 = 0
To find the solutions of the equation we will use quadratic formula,
x = [tex]\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
Substitute the values of a, b and c in the formula,
a = 2, b = -3 and c = -6
x = [tex]\frac{3\pm\sqrt{(-3)^2-4(2)(-6)}}{2(2)}[/tex]
x = [tex]\frac{3\pm\sqrt{9+48}}{4}[/tex]
x = [tex]\frac{3\pm\sqrt{57}}{4}[/tex]
x = [tex]\frac{3+\sqrt{57}}{4},\frac{3-\sqrt{57}}{4}[/tex]
Therefore, there are two real solutions.
2). Given equation is,
x² + 1 = 2x
x² - 2x + 1 = 0
(x - 1)² = 0
x = 1
Therefore, there is one real solution of the equation.
3). 2x² + 3x + 2 = 0
By applying quadratic formula,
x = [tex]\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
x = [tex]\frac{-3\pm\sqrt{3^2-4(2)(2)}}{2(2)}[/tex]
x = [tex]\frac{-3\pm\sqrt{9-16}}{4}[/tex]
x = [tex]\frac{-3\pm i\sqrt{7}}{4}[/tex]
x = [tex]\frac{-3+ i\sqrt{7}}{4},\frac{-3- i\sqrt{7}}{4}[/tex]
Therefore, there are two complex (non real) solutions.
Find the missing value of: -1 = 7 - ?
Answer:
-1 = 7 - 8
Step-by-step explanation:
An article in The Engineer (Redesign for Suspect Wiring," June 1990) reported the results of an investigation into wiring errors on commercial transport aircraft that may produce faulty information to the flight crew. Such a wiring error may have been responsible for the crash Of a British Midland Airways aircraft in January 1989 by causing the pilot to shut down the wrong engine. Of 1600 randomly selected aircraft, eight were found to have wiring errors that could display incorrect information to the flight crew.
Required:
a. Find a 99% confidence interval on the proportion of aircraft that have such wiring errors. Round your answers to 4 decimal places.
b. Suppose we use the information in this example to provide a preliminary estimate of p. How large a sample would be required to produce an estimate of p that we are 99% confident differs from the true value by at most 0.009?
c. Suppose we did not have a preliminary estimate of p. How large a sample would be required if we wanted to be at least 99% confident that the sample proportion differs from the true proportion by at most 0.009 regardless of the true value of p?
Answer:
a) The 99% confidence interval on the proportion of aircraft that have such wiring errors is (0.0005, 0.0095).
b) A sample of 408 is required.
c) A sample of 20465 is required.
Step-by-step explanation:
Question a:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
Of 1600 randomly selected aircraft, eight were found to have wiring errors that could display incorrect information to the flight crew.
This means that [tex]n = 1600, \pi = \frac{8}{1600} = 0.005[/tex]
99% confidence level
So [tex]\alpha = 0.01[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.005 - 2.575\sqrt{\frac{0.005*0.995}{1600}} = 0.0005[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.005 + 2.575\sqrt{\frac{0.005*0.995}{1600}} = 0.0095[/tex]
The 99% confidence interval on the proportion of aircraft that have such wiring errors is (0.0005, 0.0095).
b. Suppose we use the information in this example to provide a preliminary estimate of p. How large a sample would be required to produce an estimate of p that we are 99% confident differs from the true value by at most 0.009?
The margin of error is of:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
A sample of n is required, and n is found for M = 0.009. So
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.009 = 2.575\sqrt{\frac{0.005*0.995}{n}}[/tex]
[tex]0.009\sqrt{n} = 2.575\sqrt{0.005*0.995}[/tex]
[tex]\sqrt{n} = \frac{2.575\sqrt{0.005*0.995}}{0.009}[/tex]
[tex](\sqrt{n})^2 = (\frac{2.575\sqrt{0.005*0.995}}{0.009})^2[/tex]
[tex]n = 407.3[/tex]
Rounding up:
A sample of 408 is required.
c. Suppose we did not have a preliminary estimate of p. How large a sample would be required if we wanted to be at least 99% confident that the sample proportion differs from the true proportion by at most 0.009 regardless of the true value of p?
Since we have no estimate, we use [tex]\pi = 0.5[/tex]
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.009 = 2.575\sqrt{\frac{0.5*0.5}{n}}[/tex]
[tex]0.009\sqrt{n} = 2.575*0.5[/tex]
[tex]\sqrt{n} = \frac{2.575*0.5}{0.009}[/tex]
[tex](\sqrt{n})^2 = (\frac{2.575*0.5}{0.009})^2[/tex]
[tex]n = 20464.9[/tex]
Rounding up:
A sample of 20465 is required.
HELPPPPP PLEASEEEE I BEG YOUUUUUU
Answer:
D 5 This the answerStep-by-step explanation:
HOPE it HELPS
your ans. is D.........
25x to the 2nd power minus 49
Answer:
(5x+7) (5x-7)
Step-by-step explanation:
you can look up the answer on symbolab if needed
Solve for all values of x by factoring.'
x2 + 10x + 21 = 0
Answer:
Step-by-step explanation:
2x+10x=12x
12x=-21
x=-1.75
Answer:
x=-7,-3
Step-by-step explanation:
x2+10x+21
(x+7)(x+3)
x=-7,-3
3. Which two expressions are equivalent for any value of y? *
O A. 3(3y + 3) and 6y + 6
B. 3(3y + 3) and 9y + 6
O c. 9(y + 3) and 12 + 9y
O D. 9(y + 3) and 27 + 9y
Given:
The pair of expressions in the options.
To find:
The two expressions are equivalent for any value of y.
Solution:
Two expressions are equivalent for any value of y, iff they are equivalent.
[tex]3(3y+3)=3(3y)+3(3)[/tex]
[tex]3(3y+3)=9y+9[/tex]
Clearly, [tex]3(3y+3)[/tex] is not equivalent to [tex]6y+6[/tex] or [tex]9y+6[/tex]. So, options A and B are incorrect.
[tex]9(y+3)=9(y)+9(3)[/tex]
[tex]9(y+3)=9y+27[/tex]
[tex]9(y+3)=27+9y[/tex]
The expression [tex]9(y+3)[/tex] is not equivalent to [tex]12+9y[/tex]. So, option C is incorrect.
The expression [tex]9(y+3)[/tex] is equivalent to [tex]27+9y[/tex].
Therefore, the correct option is D.
Determine whether the function are inverse. F(x)=6x+l;g(x)=6x-1
What is the y-intercept for f(x) = x2 - 4x +6 ?
Answer:
6
Step-by-step explanation:
the constant is the y-intercept
ANSWER ASAP DONT SEND A FILE. IS THIS SHAPE A ROTATION, REFLECTION,TRANSLATION, DILATION OR NONE????
Answer:
translation
Step-by-step explanation:
Answer:
I think it's dilation or none
Step-by-step explanation:
Tell the error and leave if you disagree or agree.
Answer:
Step-by-step explanation:
9. disagree;
error: he should have divided 60 by 4, not subtracted. So the correct answer is x = 15.
10. disagree;
error: it should be 3x + 2 = 127 (opposite angles)
so x = 125/3
Solve for x
x-(x-2)-2(x-3)=0
Answer:
x=4
Step-by-step explanation:
bshdnbsskbewidbehhe
Find the area of the figure 2m 3m 6m 3m
ANSWER QUICK
1. Give the value of y.
3y = 51
2. Give the value of w.
w ÷ 5 = 4
Answer:
1) y = 17
2) w = 20
Step-by-step explanation:
Answer:
y= 17
w= 20
Step-by-step explanation:
In how many different ways can a red, blue, and green marker be arranged in a tray?
Answer:
6 ways.
There are one red, one blue and one green maker. So there are 3 markers they are in 3! = 3×2 = 6 ways.
Please mark brainliest! <3
Find 1/3 of 14
1. 3
2. 5
3.6
4. 2
12. If one line passes through the points
(-3,8) & (1,9), and a perpendicular line passes
through the point (-2,4), what is another point
that would lie on the 2nd line. Select all that apply.
A. (-1,0)
B. (2,5)
C. (5,2)
D. (-6,3)
E. (8,-3)
F. (-3,8)
9514 1404 393
Answer:
A, F
Step-by-step explanation:
Points A(-1, 0) and F(-3, 8) lie on the 2nd line. (Its equation is 4x+y=-4.)
Assume n is a natural number bigger than 1. what is the total number of ways you can write down as total sum of other numbers?
Answer:
report me !!! dont ask why or how
Step-by-step explanation:
Which of the following numbers makes the statement true? 3/8 > < 3/6
Answer:
2/5
Step-by-step explanation:
3/8 = 375/1000
1/2 = 500/1000
2/5 = 400/1000
2. If tan 0 = 3/4, find Sin 20
Answer:
This is an impossible question. tan(0) = 0 If this means that you are supposed to just add 3/4 to each of these, then sin(20) = 1.09
Hope that this helps!
solve x/2 + 2x/5v= 9
please I need it ASAP
Answer:
x/2+2xv/5=9
Step-by-step explanation:
The table of values represents a function f(x).
How much greater is the average rate of change over the interval [7, 9] than the interval [4, 6]?
Enter your answer in the box.
Answer:
It is 603 units greater
Step-by-step explanation:
Given
See attachment for table
Average rate of change over (a,b) is calculated as:
[tex]Rate = \frac{f(b) - f(a)}{b-a}[/tex]
For interval [7,9], we have:
[tex][a,b] = [7,9][/tex]
So, we have:
[tex]Rate = \frac{f(9) - f(7)}{9-7}[/tex]
[tex]Rate = \frac{f(9) - f(7)}{2}[/tex]
From the table:
[tex]f(9) = 3878[/tex]
[tex]f(7) = 1852[/tex]
So:
[tex]Rate = \frac{f(9) - f(7)}{2}[/tex]
[tex]Rate = \frac{3878 - 1852}{2}[/tex]
[tex]Rate = \frac{2026}{2}[/tex]
[tex]Rate = 1013\\[/tex]
For interval [4,6], we have:
[tex][a,b] = [4,6][/tex]
So, we have:
[tex]Rate = \frac{f(6) - f(4)}{6-4}[/tex]
[tex]Rate = \frac{f(6) - f(4)}{2}[/tex]
From the table:
[tex]f(6) = 1178[/tex]
[tex]f(4) = 358[/tex]
So:
[tex]Rate = \frac{f(6) - f(4)}{2}[/tex]
[tex]Rate = \frac{1178 - 358}{2}[/tex]
[tex]Rate = \frac{820}{2}[/tex]
[tex]Rate = 410[/tex]
Calculate the difference (d) to get how much greater their rate of change is:
[tex]d = 1013 - 410[/tex]
[tex]d = 603[/tex]
Answer:
603
Step-by-step explanation:
i took it
Write the augmented matrix for the following system of equations.
x - 2 = 0
2y = 4 - 2
9514 1404 393
Answer:
[tex]\left[\begin{array}{cc|c}1&0&2\\0&2&2\end{array}\right][/tex]
Step-by-step explanation:
The system of equations can be written in standard form as ...
x + 0y = 2
0x +2y = 2
The augmented matrix representation of these is ...
[tex]\left[\begin{array}{cc|c}1&0&2\\0&2&2\end{array}\right][/tex]