Estimating Mean SAT Math Score
Type numbers in the boxes.
aby Part 1: 5 points
The SAT is the most widely used college admission exam. (Most community
aby Part 2: 5 points
colleges do not require students to take this exam.) The mean SAT math score
varies by state and by year, so the value of u depends on the state and the year. 10 points
But let's assume that the shape and spread of the distribution of individual SAT math scores in each
state is the same each year. More specifically, assume that individual SAT math scores consistently
have a normal distribution with a standard deviation of 100. An educational researcher wants to
estimate the mean SAT math score (u) for his state this year. The researcher chooses a random
sample of 661 exams in his state. The sample mean for the test is 494.
Find the 99% confidence interval to estimate the mean SAT math score in this state for this year.
(Note: The critical z-value to use, zc, is: 2.576.)
Your answer should be rounded to 3 decimal places.
Answer:
(483.981 ; 504.019)
Step-by-step explanation:
Given :
σ = 100
Sample size, n = 661
xbar = 494
We use the Z distribution since we are working with the population standard deviation ;
C.I = xbar ± (Zcritical * σ/√n)
Zcritical at 99% = 2.576
C.I = 494 ± (2.576 * 100/√661)
C.I = 494 ± 10.019
Lower boundary = (494−10.019) = 483.981
Upper boundary = (494+10.019) = 504.019
C.I = (483.981 ; 504.019)
Can someone help please! I need this last question answered
Answer: [tex]\frac{x^2}{16}+\frac{y^2}{49} = 1\\\\[/tex]
This is the same as writing (x^2)/16 + (y^2)/49 = 1
===========================================================
Explanation:
The general equation for an ellipse is
[tex]\frac{(x-h)^2}{a^2}+\frac{(y-k)^2}{b^2} = 1\\\\[/tex]
where
(h,k) is the center'a' is half the total width (along the x axis)'b' is half the total height (along the y axis)Notice how 'a' pairs with the x term, so that's why 'a' describes the horizontal width along the x axis. The horizontal width is 8 ft, which cuts in half to 4 ft. So a = 4.
The vertical length is 14 ft, which cuts in half to 7 ft. So b = 7.
The center isn't mentioned (other than the fact that the actor is located here), but I'm assuming by default it's at the origin (0,0).
With that all in mind, we then get the following:
[tex]\frac{(x-h)^2}{a^2}+\frac{(y-k)^2}{b^2} = 1\\\\\frac{(x-0)^2}{4^2}+\frac{(y-0)^2}{7^2} = 1\\\\\frac{x^2}{16}+\frac{y^2}{49} = 1\\\\[/tex]
The graph is below. I used GeoGebra to make the graph.
From the graph, we can see that the horizontal width spans from x = -4 to x = 4. This is a total distance of |-4-4| = 8 feet. Similarly, the vertical length spans from y = -7 to y = 7 which is a distance of 14 feet.
A firm has a beta of 1.3 and a debt-to-equity ratio of .4. The market rate of return is 11.6
percent, the tax rate is 32 percent, and the risk-free rate is 3.3 percent. The pretax cost of debt
is 7.2 percent. What is the firm's WACC?
The WACC of the firm is 17.05%
The first step is to write out the parameters given in the question;
Beta= 1.3
Debt to equity ratio= 0.4
Market rate of return= 11.6%
= 11.6/100
= 0.116
Tax rate= 32%
= 32/100
= 0.32
Risk free rate= 3.3%
= 3.3/100
= 0.033
Pretax cost of debt= 7.2%
= 7.2/100
= 0.072
The firm's WACC can be calculated as follows
RS= 0.033+1.3(0.116-0.033)
= 0.033+1.3(0.083)
= 0.033+0.1079
= 0.1409
WACC= (1/1.4)(0.1409)+(2/1.4) (0.072)(1-0.32)
= (0.7142)(0.1409) + (1.4285)(0.072)(0.68)
= 0.1006+0.0699
= 0.1705(100)
= 17.05%
Hence the firm's WACC is 17.05%
Learn more via the link below
https://brainly.com/question/23926595?referrer=searchResults
Find the volume of a right circular cone that has a height of 18m and a base with a radius of 5.8m
Ronald types 360 words in 9 minutes.
If he types at a constant rate, how many words does Ronald type in 1 minute?
Answer:
40 per minute.
Step-by-step explanation:
360/9=40
In a standardized normal distribution the mean is ____ while the standard deviation is ____.
A. 0; 1
B. 1; 0
C. 0; 0
D. 1; 1
Answer:
A. 0; 1
Step-by-step explanation:
Required
Mean and standard deviation of a standardized normal distribution
A standardized normal distribution is represented as:
[tex](\mu,\sigma) = (0,1)[/tex]
This implies that:
[tex]\mu = 0[/tex] -- mean
[tex]\sigma = 1[/tex] --- standard deviation
Hence, (a) is true
The function f(x) = −x2 + 18x − 72 models the daily profit, in dollars, a gym makes for selling memberships, where x is the number of memberships sold, and f(x) is the amount of profit.
Part A: Determine the vertex. What does this calculation mean in the context of the problem? (5 points)
Part B: Determine the x-intercepts. What do these values mean in the context of the problem? (5 points)
(10 points)
Answer:
Step-by-step explanation:
The way to do this so as to streamline both the vertex and finding the zeros is to complete the square. That method will provide us with the vertex, and then we can continue on to factor from that form to find the zeros. Completing the square requires us to set the quadratic equal to 0 then move over the constant, giving us
[tex]-x^2+18x=72[/tex] The leading coefficient HAS to be a positive 1; ours is negative 1 so we factor out the negative to get:
[tex]-(x^2-18x)=72[/tex] Now we're ready to complete the square.
Take half the linear term, square it, and add it to both sides. Our linear term is 18 (from -18x; don't worry about the negative because squaring it makes it positive anyway). Half of 18 is 9, and 9 squared is 81.
BUT on the left we have that -1 sitting out front that refuses to be ignored. What we actually added on to the left side, inside the parenthesis, is -1(81) which is -81. -81 is what we add to the right since that turns out to be what we added to the left:
[tex]-(x^2-18x+81)=72-81[/tex] and we clean that up.
The reason we complete the square is because when we simplify the left side, we end up with a perfect square binomial found from taking the square root of x-squared, the first sign we come to, then the square root of 81:
[tex]-(x-9)^2=-9[/tex]. Move the constant back over to get
[tex]-(x-9)^2+9=y[/tex] telling us that the vertex is (9, 9). In the context of the problem that means that the gym sells on average 9 memberships a day and the profit it makes on average per day is $9.
To factor, we will go back one step to
[tex]-(x-9)^2=-9[/tex] and begin by dividing both sides by -1 to get
[tex](x-9)^2=9[/tex] and undo the squaring by taking the square root of both sides to get
x - 9 = ±3 so
x = 9 + 3 and
x = 9 - 3 so
x = 6 and 12
Those are the zeros. This means that if they sell either 6 or 12 memberships they have a 0 profit. That may sound strange, but in business it does often work like that...selling too many of something makes your company lose money (this is often due to the cost required by you to produce or manufacture the product).
Annie is opening a savings account which earns 5.2% interest compounded continuously how much will she need to deposit in the account so she has $2300 after seven years
Hi
let's call X the initial deposit.
the interest rate is 5.2 %
so each year X increase by 1.052.
so we have : X *1.052^7 =2300
X = 2300/1.052^7
X = 1612,94
please note that the deposit was rounded to the next cent. as the result would be 1612,937...
Answer:
1686.22
Step-by-step explanation:
1686.22
2300=P(1+(0.052x7))
2300=P1.364
P=2300/1.364
=1686.217...
=1686.22..
=1686 for the nearest dollar
Prove the following:
Using steps show the following is equal to 1.
Answer:um
Step-by-step explanation:
Determine whether the ordered pair is a solution of the equation. Show your work to receive credit.
9. Is (-1,3) a solution to the equation y = -3x + 10?
10. Is (7,-2) a solution to the equation x – 4y = 15?
Please show work to help me understand.
Answer:
3=3 + 10
3 = 13(NO)
x-4y=15
7--8=15
15=15(YES)
N is one of the numbers below. N is such that when multiplied by 0.75 gives 1. Which number is equal to
N?
A) 1 1/2
B 1 1/3
C) 5/3
D) 3/2
Answer:
it should be letter c 5/3 I could be wrong but I hope this help
What is the three hundred and twenty six to the nearest ten
Hi there!
»»————- ★ ————-««
I believe your answer is:
330
»»————- ★ ————-««
Here’s why:
⸻⸻⸻⸻
We are rounding the number 326 to the nearest tens.
The '2' is in the tens place, and the '6' is to the right of the digit.
Since the '6' is greater than or equal to 5, then we would round up.
326 ≈ 330
⸻⸻⸻⸻
»»————- ★ ————-««
Hope this helps you. I apologize if it’s incorrect.
The polynomial p(x) = x3 – 7x - 6 has a known factor of (x + 1).
Rewrite p(x) as a product of linear factors.
p(x)
Hi there!
[tex]\large\boxed{(x -3)(x + 2)(x + 1)}[/tex]
We can use long division to find the other roots of p(x).
We know that x + 1 is a factor, so:
Set up:
Find how many times that the first term in the divisor goes into the first of the dividend. Subtract from like terms.
x² - x - 6
x + 1 | x³ + 0x² - 7x - 6
x³ + x²
0 - x² - 7x
- x² - x
0 - 6x - 6
-6x - 6
0 0
Therefore, x² - x - 6 is another factor. We can factor this further:
Find two numbers that add up to -1 and multiply into -6. We get:
-3, 2
(x - 3)(x + 2)
The entire polynomial factored is:
(x -3)(x + 2)(x + 1)
What is the perimeter of the triangle?
units
Answer:
Does the answer help you?
Determine whether (a) x = -1 or (b) x = 2 is a solution to this equation
Answer:
x = 2 is the solution to x + 1.5 = 3.5
Step-by-step explanation:
x + 1.5 = 3.5
-1.5 -1.5
--------------------
x = 2
Select the table representing a linear function. (Graph them if necessary.)
O A. x 0
7
2 3
y 1 2 56
B. х 0
7
3
2
0
y -2 -1
-1
O c. xo
1
N
3
y 10 12 14 16
-OD. x 0 1 2 3
y 5 3 1 2
Answer:
Option C
Step-by-step explanation:
the linear equation y = 2x+10 matches with option c
Find X please
15 POINTS WORTH
Answer and Step-by-step explanation:
To find x, we must find the interior angles first, then we can find the value of x.
To find the interior angle, we need to use the exterior angle. We subtract the exterior angle from 180 to get the interior angle.
180 - 157 = 23
180 - 78 = 102
Now we need to find the last interior angle.
180 - 23 - 102 = 55
Now to find x.
180 - 55 = 125
x = 125
#teamtrees #PAW (Plant And Water) #ALM (All Lives Matter)
I hope this helps!
Answer:
the value of x is 124
Step-by-step explanation:
Paul bought a student discount card for the bus. The card allows him to buy daily bus passes for $1.70.
After one month, Paul bought 16 passes and spent a total of $35.20.
How much did he spend on the student discount card?
He spent $22.5 on the student discount card.
This question is solved using proportions.
The cost of each card is of $1.50.
Paul bought 15 passes, that is, 15 cards.
Considering that he bought 15 cards, each for $1.50, his spending was of:
He spent $22.5 on the student discount card.
Cheyenne's bi-weekly gross pay is $529.81. She sees that $18.54 was deducted for Medicare tax. What percent of Cheyenne's gross pay has been withheld for Medicare tax? Round to the nearest tenth. (2 points)
0.35%
2.2%
3.5%
Answer:
I got 3.5%
Step-by-step explanation:
Hope this helps
If 2/3 of the girls in class have brown eyes and 1/4 of the girls have blue eyes what fraction of the girls in class have neither blue or brown
what is 2x2x2x3x3 please give me answer
Answer:
The answer is 72.
I am right .
I need help ASAP please!
Answer:
Option C
We need to make the negative exponent positive.
The rule is: [tex]A^{-B} =\frac{1}{A^{B} }[/tex]
Here, A=x, B= 12
[tex]so,[/tex] [tex]x^{-12}[/tex]
[tex]=\frac{1}{x^{12} }[/tex]
OAmalOHopeO
Suppose that 17 inches of wire costs 68 cents,
At the same rate, how much (in cents) will 39 inches of wire cost?
cents
?
Cost of 17 inches of wire = 68 cents
Cost of 1 inch of wire
= 68 cents/17
= 4 cents
Cost of 39 inches of wire
= 4 cents × 39
= 156 cents
= $1.56
Answer:
17 inches of wire costs 68 cents,
Step-by-step explanation:
x=234
b=456
1/5 divided (-5/7) Can someone please help with this equation and show work
Answer:
-7/25
Step-by-step explanation:
1/5 ÷ -5/7
Copy dot flip
1/5 * -7/5
-7/25
Chen rode his skateboard 3/3/4 miles in 34 of an hour.
What was his average speed in miles per hour?
_[blank]_ miles per hour
Answer:
5 miles per hour
Step-by-step explanation:
3¾ ÷ ¾ =
15/4 ÷ ¾ =
15/4 x 4/3 =
15/3 = 5
Solve the formula for t
V = 4(3.14)ct + 6(3.14)c^2
9514 1404 393
Answer:
t = (V -6(3.14)c^2)/(4(3.14)c)
Step-by-step explanation:
Isolate the term containing t, then divide by the coefficient of t
[tex]V=4(3.14)ct+6(3.14)c^2\\\\V-6(3.14)c^2=t(4(3.14)c)\\\\\boxed{t=\dfrac{V-6(3.14)c^2}{4(3.14)c}}[/tex]
find the value and express it in standard form : 5×10^8×2×10^11
Answer:
1*10^20
Step-by-step explanation:
5×10^8×2×10^11= 5*2*10^(8+11)= 10*10^19= 10^ (1+19)= 10^20= 1*10^20.
please mark this answer as brainlist
find the equation of the line which is parallel to the line 5 x + 4y = 18 and makes an intercept of 2 units on the x-axis
Answer:
[tex]{ \underline{ \sf{equation \: is : \: y = - \frac{5}{4} x + 2 }}}[/tex]
Step-by-step explanation:
[tex]y = mx + c \\ 4y = - 5x + 18 \\ y = - \frac{5}{4} x + \frac{9}{2} [/tex]
since it is parallel, the gradients are the same; m = -5/4
[tex]y = - \frac{5}{4} x + 2[/tex]
Answer:
y=-5x+2
Step-by-step explanation:
x intercept=2
points will be (2,0)
slope of given line:
4y=-5x+18
y=mx+c
comparing equation:
m=-5
lines are parallel so given slope is equal to required slope.
using point slope form:
y-0=-5(x-2)
y=-5x+2
Solve for the value of x
Answer:
Step-by-step explanation:
This is the Law of Cosines. Use the following formula:
[tex]5.1^2=3.3^2+3.3^2-2(3.3)(3.3)cos(x)[/tex] and simplify to
26.01 = 10.89 + 10.89 - 21.78cos(x) and a bit more to
4.23 = -21.78cos(x) and finally to
-.194214876 = cos(x) and use the 2nd button along with the cos button to find that the missing angle is 101.2 degrees
find the LCM of 220,440,660 by common division method
Answer: LCM = 1320
Step-by-step explanation:
2 | 220, 440, 660
2 | 110, 220, 330
2 | 55, 110, 165
3 | 55, 55,165
5 | 55, 55 , 55
11 | 11, 11, 11
| 1, 1, 1
= 2 × 2 × 2 × 3 × 5 × 11
= 1320
Therefore the LCM is 1320
Must click thanks and mark brainliest
